Soon to be 1 more 1984 VF700F back on the road....hopefully!

Just picked up this 1984 VF700F on Sunday. Yes, I know all the bad stuff about the cams....but I just couldn't pass this one up. It's a one owner since new bought in Feb 1986, I have the original title from the Honda dealer with 000001 mile listed on it. Guess it sat in the showroom for few years?

It appears to be all original to me except for the mufflers, tires and battery. I even have the tool kit with all the tools and the bag, plus the owners manual and pouch. He also had a service manual so I have that too....bonus! 10,550 miles on the clock.

From what I can tell the owner had the initial 600 mile service done by Honda, then changed the oil/filter (valvoline racing 20w-50 is noted as being used) and coolant a few times and that's it. Looks like he skipped the 8,000 mile service but I'm not sure. So I don't know if the valves have been checked since 600 miles.

The bike was in the care of his step son when I got it. The step son had replaced the fork seals and front brake pads. It looks to me like he has the front end wonky....one fork is higher than the other causing the tire to be kicked over to one side! I'll be looking into that very soon! I kinda wonder if he lost the fork stop rings when he had the forks out and so had to guess as to their height? I'll find out soon enough. Luckily he never rode it after putting it back together, he said he never rode it more than up and down the street once.

The body work is mint, I cannot find a nick, scratch or ding anywhere on it....even the lower cowl. It was stored with a full tank of gas so there is ZERO rust in the tank! A first for any bike I've owned. The bad is that the rest of it has corrosion, nothing too serious but its not pretty. All the nuts and bolts, aluminum...all that stuff. We live near the coast and to me it looks like it was ridden to the beach and then never washed.

When I got it it would only start and run for about 1-3 seconds and then die, owner showed me, give it a few seconds and it would restart, idle for a few seconds and die. It had been sitting idle in his garage for a few years before he decided to sell it.

Some pics.....

 

I've been lurking here for about a month now reading all I can find about all the bad stuff with these gen 1's. Even with all that I couldn't pass up such an original low mileage unmolested bike, especially for the price, under $500.

First thing I did was to bypass the fuel pump and filter to see if that was the cause for it only running for a few seconds at a time. I can feel the fuel pump click once for each revolution when cranking so I suspect its the filter. But for now I bypassed both with a new filter in place of the pump/original filter. Started right up and continued to idle without dying but it will only run with full choke and if I touch the throttle it dies instantly. Knowing about the top end oiling issue I only let it idle at 1K for about a minute before shutting it off. Just long enough to verify that either the pump or original filter is causing a restriction.

So time to pull the carbs, that was fun. They are off and on the bench now, I was disappointed to find that someone has been in them before. I was really hoping this bike was less touched since leaving the factory than it appears to be. See the XO signature on the carb bowls, there appears to be D's marked on the tops....




I put the blue numbers on them, to keep everything straight and with its correct carb. I've only pulled the bowl off the first carb and there is some crud in there. Green crusty stuff blocking the jets, but luckily it just wipes off, seems to be no permanent corrosion inside the carbs so far! Hopefully the other three are ok.

I also decided to take a look and see why the right side fork rebound damping knob was so hard to turn.



Found this...looks like the step son did some damage when getting the cap bolt off for the fork seal replacement. Rounded it off and also reinstalled the fork so the 1 setting was to the left and not straight down like its supposed to be. So that and the uneven heights of the forks....Kinda scares me as to what else I may find wrong with the forks. I'll be going back thru them for sure. He says fork seals and front pads are the only thing he ever did to the bike so hopefully there wont be any more surprises past the forks. To be fair the service manual says nothing about removing the white plastic piece before removing the cap bolt, or anything about reinstalling the fork so the numbers are in the correct positions. The service manual seems to be sparse in quite a few areas. I would have thought Honda would have had a better manual than this.

I got the cap bolt all cleaned up and the damping knob turns very smoothly now.

While I have the carbs off I plan to pull the rear valve cover and take a look at the rear cams. Check/adjust clearance if needed, .006" using the two shim method correct? I'm going to check the front ones too, but probably will put the carbs back on first to keep the thing more together.

If I find cam damage then I will have to decide what to do. I know about Megacycle, but its pricey. Hopefully the cams are ok, its a chance I decided to take when I bought it.

My plans if the cams are ok is to run spectro, redline, motul....(one of those oils correct?) and keep a good eye on checking the valves. Should I keep 20w-50 in it? I live on the Texas coast, its very hot here.

Should I pull the oil feed line, the one that sits under the carbs with the banjo bolts, and make sure its not clogged or restricted? I'm not planning to do an oil mod, I'm going to run good oil in it, change it often and keep my valve clearances in check. It's not like this is my only mode of transportation or anything, I have three other bikes including a '77 KZ1000 to ride around on also. If the cams go then I'll decide what to do then.

 

When you get it all back together run 12 volts direct to the fuel pump for 30 seconds or so. This should prime the system and save you a lot of cranking (this is good time to check for fuel leaks of course).

All-in-all a great find if you ask me. Glad to see that you rescued her...

 

You can tell pretty quickly when a bike is in the right hands...and it seems clear that's the case here. Good on ya. The bike looks great, wish I could find one.

The cams may/will be the deciding factor. There's a guy on another forum who just had his cams reground, I'll shoot you the link if it comes to that. The carbs are easy to do just know the front and back carbs have different components so keep each carb parts separate.Read this when the time comes and welcome aboard.

***DO NOT remove the aluminum plate that holds the 4 carbs together. You can do a pretty good job of cleaning without separating the carbs. The guide shows them completely apart but you don't/shouldn't have to get that crazy.



From V4BBS, for quick reference...
"The V4 engines use 4 constant velocity (variable venturi) carburetors to supply fuel to the engine. The constant velocity refers to the air speed through the throat of the carb. The velocity is controlled by a slide mounted to a diaphram. The diaphram is sensitive to vacuum created by the flow of air across a hole(s) in the needle end of the slide. As the engine speed increases, the vacuum above the diaphram increases due to venturi action and the slide is raised.

There are three circuits (paths) in the carb.
The starting circuit (choke) provides extra fuel when the choke is open. It uses a fixed jet and a choke plunger to control the flow of fuel to the port in the carb throat. The restriction is the fixed jet at about 0.021 inches. The choke plunger also provides an air bypass around the throttle plate to increase the engine speed during warm up.

The low speed circuit provides the primary fuel for operation below 4000 to 5000 rpm. When the engine is pulling vacuum the fuel is drawn through a passage to the low speed needle valve, and then to a large hole on the bowl side of the throat on the engine side of the throttle plate. The needle valve controls flow to the large hole. This path also feeds the 4 tiny holes on the float side of the throat and under the throttle plate. Both paths continue to function at all engine speeds. The restriction is the low speed needle or the low speed jet.

The high speed circuit provides fuel above 4000 rpm. It uses a fixed orifice and a needle connected to the slide to control the flow of fuel to the needle valve opening in the carb throat. As engine speed increases the slide raises the needle and allows additional fuel to flow. The restriction is the needle valve on the slide. Since the needle valve never completely closes, the circuit provides fuel at all engine speeds.

It should be verified that fuel is getting to the carbs. Verify you are getting a flow of fuel at the inlet hose to the carbs. No flow can be caused by delivery problems due to tank venting, plugged screen in the tank, pinched hoses, fuel pump problems or fuel filter plugged. Or you could be out of gas.

The main symptoms of carb trouble are.
1. Hard cold starting that is caused by restricted choke circuit, low speed circuit or improper fuel level in the float bowl. Failure modes that cause this are.
a. Plugged low speed jet. The jet must be removed and cleaned.
b. Plugged choke jet. The jet cannot be removed, it must be cleaned in place.
c. Plugged low speed circuit and choke circuit passages from the jet to the carb throat. The carburetor must be removed and the passages cleaned.
d. Improper fuel level in the float bowl. The float valve and screen must be removed and cleaned. The float must then be set to the correct level.
e. Improper setting of the low speed needle valves. In most cases resetting them to the factory recommendation will be satisfactory.

2. Poor idling and hesitation when accelerating up to 4000 rpm caused by restricted low speed circuits or improper fuel level in the float bowl. . Failure modes that cause this are.
a. Plugged low speed jet. The jet must be removed and cleaned.
b. Plugged low speed circuit passages from the jet to the carb throat. The carburetor must be removed and the passages cleaned.
c. Improper fuel level in the float bowl. The float valve and screen must be removed and cleaned. The float must then be set to the correct level.
d. Improper synchronization of the 4 carburetors. They may synced while on the engine using vacuum gages or mercury sticks.
f. Improper setting of the low speed needle valves. In most cases resetting them to the factory recommendation will be satisfactory.

3. Poor operation above 4000 rpm caused by improper slide operation or improper fuel level in the float bowl. Failure modes that cause this are.
a. Ripped diaphram. Ripped diaphrams must be replaced, usually with the carbs off the bike.
b. Leaking diaphram. If the diaphram is not seated correctly in the cover it will leak air and defeat the vacuum action.
c. Sticking slide. The slide must be removed and any contamination removed.
d. Choke valve not closing completely.
e. Incorrect high speed jet or emulsion tube installed. Verify correct parts.
f. Incorrect spring installed over the slide. Verify correct springs.
g. Incorrect high speed needle installed. Verify correct needle.


Carburetor Cleaning and Rebuild

There are 3 approaches to cleaning the carbs.
Use an additive in the gas tank such as Techtron or Sea Foam.
Do the disassembly and cleaning yourself.
Send them to a professional for a super cleaning.
The additive route sometimes works if the plugging of circuits is not too bad.
The do it yourself method will achieve well functioning carburetors that looks like they did when you took it off.
The professional cleaning by Billy Carr will make them shine and function like new with the added advantage that he has any needed replacement parts. BBS friendly carb cleaning service

To quote Billy, "being the local carb guy means I get mine either way. I rebuild them... I get paid. You do them yourself with my cheap carb kit ... I get paid. Buy the carb kit and in a few hours and you can have a resealed long lasting set of carbs. Never be afraid to delve in to a set of carbs unless you do not possess the simple ability to tell which end of a combination wrench is which. Worst case scenario is you mail me a bucket full of parts when you realize you got in over your head. Saves me teardown time."

Sample of his work.





Helpful hints if you do them yourself.

Take photos of the carbs installed, cable routing, removed still on the plenum from all angles. You will treasure them when you put things back together.
Remove all 4 carburetors and the plenum (air box) as an assembly.
Drain the fuel from each carb through the drain nipple by opening the needle screw in the bottom of the float bowl.
If the carb rack (all 4 carbs bolted to the plenum) is dirty clean it with a degreaser before you start to take things apart.





When you disassemble your carbs keep the parts separated by individual carb as they are different from front to rear in many cases (baby food jars are great). Note, after 30 years and many owners the parts may not actually be in the correct location. Always refer to manual for the correct placement and part. The model number will be stamped on the flange above the float bowl.
Do not be afraid to use a permanent marker in an out of the way spot to keep the carbs straight (number the baby food jars too). They are numbered #1- #4 left to right as you sit on the bike.
If you do not split the rack you will not have to hassle with the linkages and the throttle plate synch will be much easier. You will not be able to change the fuel and air tube o-rings however, your call.
Use a good #3 Philips tip screw driver bit or impact bit to loosen all screws. Tap each one a couple of times with a hammer and bit before you try to loosen them
Your work area should someplace where you can track down parts that may escape you.

Do It Yourself Rebuild

Buy a carb rebuild kit from Billy C at BBS friendly carb cleaning service
It has everything you need plus a DVD filled with information.


One carb at a time, remove the 4 screws that hold the float bowl on. Check condition of the o-ring seal. If hardened, get new ones. If they have never been replaced they will be hard and flat.




Remove and clean the drain plug and clean the drain nipple if plugged.
Remove the pin holding the float in place, remove the float and needle.
Remove and check the condition of the needle seat and screen.
Remove the high speed jet and holder (emulsion tube). Make sure all holes are clean.
Remove the low speed jet. Make sure all holes are clean especially the one through the center, clean with a 0.015 inch wire or #79 pin drill for 38 size jets. The size of the jet is stamped on it. 38 stands for 0.38 mm or about 0.15 inches.
The choke jet cannot be removed, pressed in. Clean the hole through the center of it, clean with an 0.021 inch wire or a #75 pin drill.
Inspect all passages and blow air or a solvent through them. Look into each hole with a good light and a magnifying glass.

Login 20pc Drill Bits #61-80 and Pin Vise





Remove the low speed needle from the side of the carb just above the float joint. It may be covered with an aluminum cap to prevent tampering. If it is, drill a 1/8 inch hole in the cap, drive in a sheet metal screw a couple of threads and pull the cap out. Before unscrewing the needle, turn it in counting the number of rotations until it seats lightly. The needle will have a spring, flat washer and o-ring behind it, remove them.
Inspect all passages with a good light and a magnifying glass and blow air or a solvent through them.






Remove the choke valve by removing the black plastic nut, the linkage plate, the black linkage sleeve and spring. Work it out as an assembly. Be careful, the black nut is fragile.
Take some more pictures of where all the linkage goes.




Blow air through all the passages to clean, including the choke jet.

On the other side of the carb, remove 4 screws holding on the chrome cover. Be alert, it is spring loaded.
Remove the diaphram cover and spring.
Remove the diaphram slide assembly. Carefully inspect the diaphram for any tears or cracks. If any found, big and expensive problem to replace. Clean the slide and its bore of any residue. Don't use carb cleaner on the diaphrams, it will damage them. Use a 0.018 inch wire or pin drill #77 to clean the brass orifice located under the diaphram cover. This orifice appears to be a drain for any fuel accumulated in the top of the diaphram.

With all the jets, needles, slides and chokes removed, blow air through all the passages including the choke jet. Blow air through the small ports in the carb throat to verify that they are clear. Soaking in a cleaner may now be done safely.




***THIS IS NOT MANDATORY, I WOULD SKIP THIS UNLESS YOU HAVE FUEL LEAKAGE FROM THE TUBES***

Now is the time to replace the o rings on the fuel rail if you plan on doing it. Be very careful with the tubes as they can be broken with sideways pressure. The o rings are included in the Billy C kit.
Use a quality #3 Philips head screw driver to loosen the 8 screws holding the carbs to the plenum. Tap them with a bit and hammer to break them loose. Leave all screws in place until they all have been broken loose.
Take pictures of all the springs on the throttle linkage.
Remove the 8 screws and remove the plenum. There are locator dowels on each carb that may require prying out for separation. BE CAREFUL the sync and shaft springs will fall out when you separate the carbs. You did take those pictures right? The tubes are unique so keep track of what goes where.
Remove the o rings from the tubes and replace with the new ones.
Clean the holes that the tubes insert into. Did you notice that the fuel path runs straight through the bottom of all 4 carbs?
Carefully insert the fuel tubes back into the carb bodies along with the vent tubes if your model has them. Do not let the o ring roll out of the groove. The throttle adjuster plates and shaft springs must also be lined up for each carb. Do not worry about the sync springs at this point.
Replace the plenum with new socket head cap screws M6-1.00 x 20. You do not want to mess with the Philips the next time. They are available at most hardware stores for about $.50 each. Evenly tighten the screws making sure that the tubes and shafts are not binding. Boiling the air funnels makes them easier to install. Old ones shrink and are a pain in the ass to get in place. Make sure the line on the funnel is between the two index lines on the airbox.

When you are satisfied that everything is clean, begin reassembly.

Assemble the diaphram slide assembly into the carb, make sure the hole(s) in the diaphram align with the holes in the carb.
Assemble the spring and cover. Short vacuum piston springs install in the rear carbs, long springs install in the front carbs. Make sure the diaphram seats into the groove. Tighten 4 screws. To test seating, hook a shop vac up to the engine side of the carb and open the throttle plate. The slide should rise, then fall when the throttle is closed. If it doesn't the diaphram is not seated.





Gently flex the floats to check for cracks. They like to crack where the lattice meets the float---and then they fill up with gas. You'll notice the float full of fuel if you tear down quick after carb removal. Otherwise you won't know without careful inspection.

Inspect your float needles. The rubber tip on can pull out of the metal needle and bind up the valve.

Carefully clean the choke plungers. It makes them operate smoother and prevents them from hanging up. Some fine emery paper works well for this. Inspect the end of the choke valve for the condition of the rubber insert. If it is badly worn in may be removed and flipped over. Replacements are not available.
Assemble the high and low speed jets in the carb tightly. Verify the correct size is used in the correct location. The fuel emulsion tubes that the main jets thread into are different between front and rear carbs. There are low drilled holes and high drilled holes in the tubes. The tubes with the holes located furthest away from the main jet install in the rear carbs.








Set the float height by holding the carb on its side until the float just stops closing. Then measure the distance from the top of the float to the bowl surface. If you lay the carb down it will distort the reading. Adjust the height by bending the metal tab on the float. A dial or digital caliper back end works well for setting the height. If you get different readings on each side of the float, use an average of the two readings.
Install the float bowl with gasket and 4 screws tightly. Tighten the drain plug in the bowl.

Assemble the spring, washer and o-ring in that order on the slow speed needle. Screw in the needle assembly until it just bottoms out. Then open the number of full turns recommended.





Assemble the choke valves, lifter arm, spring, black sleeve, black nut and linkage plate. Don't break the plastic nut. Test by moving the choke lever (where the cable attached) and verifying that the valve opens about 3/8" and closes with a slight clearance between the head of the valve and the fork. You may need to wait to do this until all 4 valves are assembled. If they don't function correctly, adjust the linkage by bending.

Install all sync springs at this time. Remember there is a spring on the sync screw and a spring between the two tabs. Use those pictures you took for reference.













Bench check the sync of the carbs.
#1 carb is adjusted with the black idle knob. Place a 1/8 inch wide strip of printer paper between the throttle plate and bore on # 1 carb. Adjust the black idle knob until there is a slight drag on the paper.
Next, place a strip into #3 carb. Adjust the screw on the linkage for the same drag. There must be 2 springs on the adjuster for it to work properly. One on the screw, one in the linkage.
Verify that the linkage between the front and rear carbs is in place and that the bushing are tight.
Next, place a strip into #2 carb. Adjust the screw on the linkage for the same drag. There must be 2 springs on the adjuster for it to work properly. One on the screw, one in the linkage.
Next, place a strip into #4 carb. Adjust the screw on the linkage for the same drag. There must be 2 springs on the adjuster for it to work properly. One on the screw, one in the linkage.

An alternative method uses the small hole in the carb throat to set the plates. The plates should be set so that half the hole is visible. The hole is opposite the paper shown in carb #1.





Cycle the throttles to make sure the settings repeat.

With the carbs mounted to the plenum do the following before you put them on the engine
1. Do a bench sync and make sure all the little springs are in the throttle linkage. Make sure that the linkage bushings are not worn out, this can cause sync problems. All 4 throttle plates should move at the same time.
2. Move the choke lever and verify that all 4 choke valves are opening and closing fully. Adjust (bend) linkage to get them all working and have clearance at the valve to fork when closed.
3. Hook up a shop vacuum to the engine side of each carb. Open the throttle with the vacuum running. The slide should open, and close quickly when the throttle is closed.
4. Some people fill the carbs with fuel before installing to make sure there are no leaks.

Now is the best time to change the o-rings on the 2 coolant tubes in the V of the engine. It can be done with the carbs in, but not easily.
After reinstalling the carbs on the bike and before you hook up the fuel line, FLUSH the fuel lines to remove any debris. Or you may be doing this procedure again.

After reinstalling the carbs on the bike a sync of the carbs should be done using gages. This will compensate for the minor differences in flow to each cylinder. With a good bench sync, most people find that there will not be much change needed. Do this sync in the same 1,3,2,4 order.

The manuals describe an idle drop method to adjust the low speed needles. It is somewhat difficult to do and the results people have had are varied. Give it a try if you want, but most people get back to just about the recommended settings. I prefer to start with the recommended and then close each needle a quarter turn in. Ride the bike and verify that acceleration has not been affected. Try an additional quarter turn and verify acceleration. If performance falls off, go back one step. This leaning of the mixture procedure will improve your mileage and improve hot starting in high temperature conditions."

 

Thanks guys...as for being in the right hands...I'll do my best with it! I do like to take my time and make sure everything is done right, to me fixing them is the fun part.

I know this isn't exactly a desirable model but I couldn't pass it up because of its overall condition, originality, and single owner history. Can't beat that. I doubt many of these models have bodywork in as good of condition as this one. However....the corrosion under that shiny bodywork is not so pretty....have to deal with that later.

But for now I had a few hours last night to get into the carbs....the insides look good. There was crud in them, each jet had some junk come out of it, but no corrosion. I'm going to empty the garnet out of the blast cabinet and throw some soda in there to clean up the outsides....I plan to pull and do the valve covers too while the soda is in there.

I'll try and get some before/after pics up later.

As for direct wiring the fuel pump to test/purge...do I go green to negative and black to positive on 12v battery and thats it? The manual shows some fancy setup with a diode? I'm definitely not an electrician.

 

Decided to pull the rear valve cover to take a look at the cams before going any further.....well crud....#3 intake.....



Haven't checked clearances or even pulled the front cover yet, kinda wondering if I should go any further or just pack it in.

 

PM sent.
Bummer. That can get to be expensive. At this point I'd pull the front cover as well and check it out as well.

 

I'm not ready to start parting it out yet.

From the pics I have seen of bad cams, mine looks nothing like it....at least not yet. The damaged area on mine is tiny, and feels smooth and looks burnished...not rough and sharp. Maybe this happened right out of the gate and it wont get much worse....I can afford to take the chance.

I'm going to pull the front cover and hope I don't find anything worse than what I've already found. If not then I'm going to put it back together, put some good oil in it, make sure to not idle it very long and put about 1,000 miles on it. Then pull the covers and take another look. If the damaged area stays small then good....if not I'll have to decide then, I figure after 1,000 miles on it I will know if I want to spend the $$$ to fix the problem for good. Talking megacycle....yes they still do it, for $1,200 for the four cams and 8 followers.

But I haven't even had this bike running yet....I still don't know what other problems I'm going to find.

I have read on here people recommending Spectro oil, which exact one are you guys running, they have about 40 different oils? Also I am better to stay with 20w-50 or go a little thinner like 10w-40? Wondering what weight pumps up to the top end better in these engines? Cold temp is not a factor for me.....I don't ride when its cold. ;-)

 

Finally got the carbs squeaky clean and back together. Not on the bike yet...but they are in one piece again at least. Not really looking forward to putting them back on based on how hard it was to get them off. I'm going to try the bedroom lubrication and pan of hot water trick and see if that helps. Get them in the front first then glide them into the rear. Ha!

I checked the valve clearances on cylinder 1 and 3. I based my clearances on the largest size feeler gauge I could get to go under both sides at the same time. Had to go buy a second set of feelers. I also just turned the crank until the nose was pointed directly away from the follower, didn't do like the book says and set to 1,3 TDC or whatever. Basically set them so the hole in the base circle was in the middle of the follower.

On cylinder #1 I got .005" on both intake and exhaust....left them alone.

On cylinder #3 I got .006" on the intake (the one with the bad cam lobe) and .003" on the exhaust.

I adjusted #3 exhaust and decided to try the .004 between the lobe/rocker technique and nailed it the first time! Couldn't believe it...didn't think it would be that easy. I now have a snug .006 on the #3 exhaust. I held the adjusting screw and snugged the lock nut with a regular 10MM wrench, then turned the crank until the valves were open to put pressure on the adjusting screws, and using a GOOD USA made torque wrench set them to 170 inch lbs. I know the book says 15 ft lbs or 180 inch lbs but 170 felt tight enough to me! I was getting scared putting that much on them.

I know cylinder #1 intake and exhaust are a little on the tight side at .005 but I'm going to be checking these again in 1,000 miles or less to see how the cam is looking anyways. Any changes and I'll adjust them then.

So next thing is to get the carbs back on and then time to pull the front valve cover, which includes pulling the radiator! Yea!

If I don't find anything horrible on the front set of cams then maybe I can go for a ride! After I figure out whats up with the front forks anyways. Those crooked things.

 

That sucks oot loud aboot the cams, Mega Cycle will resurface the cams and followers but it is very expensive and a pain but your bike is clean enough that you can justify the hassle and wallet bleeding. Hunting used is another option. I think it will start up fine with new boots and cleaned carbs, just prime the system. Good luck sparky.

 

To be honest, that lobe doesn't look that bad to me. I have seen worse on smooth running bikes. The follower is more of a tale tell for me. It's definitely not going to get better and down the road it will be bad.

There's a guy on VFRD who just did a set by Megacycle on his 750. Pm him for the details.

http://www.vfrdiscussion.com/forum/index.php/topic/77699-my-old-girl-is-getting-a-makeover-83-vf750f/page-3

If you look at his first picture of the cam lobe you can see one of the big problems with these early cams and it's not oiling related. You can see defects in the casting that looks like bubbles, that's exactly what they are. Impurities caused voids in the metal during casting that formed just below the surface. After final grinding of the profile, there was VERY little material covering these imperfections and the slightest wear from poor hardening opened them up. These voids however probably aren't going to beat up the follower because they are recessed. Poor tolerances in the top end helped the damage further. Line boring and oil holes in the lobes helped curb these issues somewhat.

There are perfectly good 1st gen cams out there with lots of miles on them, some even on Ebay. It's a crap shoot on whether you'll get a bad set or not. I've seen just one cam lobe be bad and the rest look new on the same bike so who knows.

Seems like you know what you're doing so any decision on moving forward will likely be an educated one. Keep us posted.

 

Sparky? Lol.

If replacing the carb holders on this bike (boots) is anything like on the KZ's I usually mess with it will make a HUGE difference! But....I'm going to put it back together with the originals for now. I don't want to put any money into this bike yet, I want to get it running and ride it first and then decide if I think its worth it.

Do you guys think 1,000 miles is a bit much to go before having another look at that cam? Maybe just 500 instead? It's not hard to pull the rear cover anyways.

I also agree that oil is not the only issue, or even the biggest. Based on some of the stuff I have read here I expected to find a completely dry top end when I took that valve cover off, but instead there was quite a bit of oil up there. Way more than I expected. My guess would be poor chrome adhesion on the followers and poorly made cams. If the followers and cams were good from the beginning we wouldn't be having this discussion, low oil flow or not. I would bet there was at least one or more Honda engineers back then that were wanting to use bucket valves from the start. Was there a reason they chose not to? Seems strange to me on a motorcycle/engine that Honda was using as a showcase for the latest and greatest that they chose to use rocker arm/tappet valve setup.

But I'm for sure no expert on the subject...just kinda guessing at it.





Is the Honda HP4 oil decent to use? No-one around here carries Spectro but the Honda place has Honda oil. I know to look for something with a decent amount of ZDDP.....but I don't think zinc can be the only thing to look for? Should I look for a racing or off road use only type oil? 20w-50 my best bet?

This is just to get the bike thru a few hundred miles or so until I can get some Spectro....but again....I don't want to throw $50+ in oil in the thing if it ends up not running. I know that sounds cheap, and it is, but I just don't want to throw money into a big pit if I don't have to.

 

Got the carbs back on, I was all worried it was gonna be almost impossible to get them back on, but it ended up being easy. I made sure the clamps were all the way out, put some lube inside the boots and those carbs popped right back on there no problem. I put the fronts on first, then had to push the front of the back boots back to get them lined up better and in they went. Used two very dull screw drivers as shoehorns but it didn't take much, the chamfer on the carbs helps quite a bit.

I filled the carbs with fuel while they were still on the bench to check for leaks. No leaks after a few hours so back on they went. Jumped the pump to prime the system and she started right up and was ready to come off choke just about right away.

Engine has a pretty good valve tick and using a broom stick it sure sounds like its the valve I adjusted. I had a snug .006" and a .007" would not fit but I may pull the cover and recheck them again. It was nice of Honda to use rubber gaskets so we can reuse them, makes checking our junky cams over and over so much easier. Ha.



With it running so well I decided it was time for a test run up and down the street, got the bike turned around, pulled in the clutch, put it into first and it lurched and died. No clutch! Checked the master and it was a little low....topped it off and bled it, feel resistance at the lever.....still no clutch.

Pulled the slave cylinder and it was packed with what looks like crystallized brake fluid, if I had to guess??? It looks like it was keeping the piston from moving out to push the push rod.

I've got it off right now cleaning it up, piston was free inside the cylinder so I pulled it out and polished the bore a little. Hopefully that's going to fix it. I took a pic of the crud and I'll post it later. Seal looks fine, but there is evidence it was leaking, the crud inside there and paint gone on the sprocket cover under the slave cylinder. If it still leaks I'll replace the seal.

 

This is what I found on the backside of the clutch slave cylinder! It cleaned up very easy and the bore and seal looked fine so I put it back together. I didn't take a cleaned up pic, should have.

Obviously it was leaking because of all the crud in there, but it seemed to seal up fine after cleaning it up a bit. I did give the bore a little polish with some regular polishing compound. I'll be keeping an eye on the weep hole for fluid and probably pull the slave after a few weeks and check it anyways.

Got it back on there and still no clutch! Plates were stuck, put it in gear, held the lever in and rolled it back and forth until it broke free. Didn't take much.

So finally got to go on the first ride, just up and down my street for now. Seems to be running really well, besides that valve tick! It's for sure coming from the valve I adjusted so I'll need to recheck that ASAP. Luckily its the rear so its easy to pull the valve cover.

The temp never got above the skinny part of the stripe on the dash gauge. Is that normal or should I check the temp sensor? It was running for about 10-15 minutes total, up and down the street about 20mph. I was wanting to make sure the fans would come on but it never got hot enough. They come on when needle is about 2/3 up the temp gauge correct?

 

Nice looking bike! Keep the updates and pics coming.

 

I haven't had much time to mess with it the past few days. But had a little time Sunday so I pulled the front valve cover to take a look at the front cams. Didn't check clearances yet, just wanted to take a look at the cams.

I was really expecting to find more cam damage but luckily the fronts look mint! So it's just the #3 intake lobe showing pitting. That's good...that gives me some hope that if I run good oil, change it regularly, don't let it idle excessively and keep up with the valve clearance adjustments that I can keep the other cams in good condition.

I'll just check the bad one frequently and hope the wear doesn't get too bad too fast.

I think I'm going to try amsoil in it. I know people have really good luck with golden spectro but no-one around here sells it. I can get amsoil at the Honda dealer.

 

Checked valve clearances on front two cylinders.....

Using the book method, rotate to TDC of 1.3/2.4 and check cylinder 1,2,3 etc....I got....

#2 Intake .005"
#2 Exhaust .006"

#4 Intake .004"
#4 Exhaust .005"

Using the method of just pointing the nose opposite from the follower got....

#2 Intake .007"
#2 Exhaust .006"

#4 Intake .006"
#4 Exhaust .006"

Guess I can take from those measurements that no adjustment is needed?

I went ahead and pulled the front forks while I was at it, they were crooked when I got the bike. I went by the service manual to re-install and they look straight now, not sure what the PO did to get them crooked. I think he just had one fork higher than the other, but the stop rings were in place so I'm not sure. Maybe he tightened bolts out of sequence?

The fairing looked wonky too....turns out the fairing stay was just a little crooked, loosened up the bolts on the sides, held it straight and tightened them up. Bike sure looks better now, it looked funky from the front before with the crooked tire and fairing. Easy fixes that I was worried might be something big.

I did find, with the front off the ground, that the steering has what feels like a detent right in the center, I don't think that's normal? Steering stem bearings? Bike sat for a long time on its center stand without moving, could that cause that?

 

Any updates on this bike? How are the cams holding up? Pics?

 

I only have 350 miles on it since I bought it. I have checked the rear cams about 4 times and the fronts 2 times since I've had it. Overkill, probably, but just wanted to keep a very close eye on it right at first. Plus it took me a few times to get the valve clearances set where I wanted them so I was in it anyways. I was using the book method to set the clearances but that way I was having very loud valve ticking, finally went back and set them using nose up (loosest spot) and now it sounds great!

No change in the one bad spot in that single lobe in 350 miles, fingers crossed! I'll just have to keep an eye on it. I'll probably extend checks from -100 miles to 500ish miles now and see how it looks then.

What do you want pics of? Fresh pics of the bike in general or the cams? I have done lots of cleaning on it, polished some bits and cleaned the rest. I'll get some fresh pics up soon. I need to ride it more! But it went from summer to winter overnight this year. It's usually still warm in November and December but we've already had a few freezes!

 

Any pics will do. I'm just being nosey and looking for inspiration. Thanks