My 1st carb rebuild has begun! 86 VFR750

Ok, so today marked the beginning of my 1st major project on my '86 750. I was a bit nervous at first, but figured I'm gonna be workin on tons of bikes over the next year while I'm in school, so I might as well just jump in! I have the tools, the parts are on their way... no reason to NOT start disassembly of her and get the carbs cleaned and ready.

So far, I got the plastics, seat, tank and air cleaner off of her. It got dark before I got to remove the carb assembly, so I'm gonna hold off till the morning for that. So far she is pretty damn clean from what I can see. There were many points on the plastics that showed being repaired underneath (although the outside is perfect in most of those areas). I wonder who the hell did the work on the plastics, cause I'd love to get them to fix the existing cracks and make em look new again!

Some points to note so far:

The original owner had his California registration (exp 2001) still in the manual slot inside a Priority Mail envelope, and there was no tool kit

The pre-filter at the heat shield is brittle and totally corroded - I'm surprised she was able to breathe at all!

The spark plug well on #1 has some nasty fuel residue around the plug - didn't check #4 yet.

The air intake to the venturi's isn't in bad condition, but does have a residual film on it that I think will come off during cleaning. My buddy showed me his friends GSXR carb intakes and they were 10x's worse than this, so I feel pretty good about it so far.

I'm takin pics as I go so I have a record of what I've done, and also to show you guys in case you see something I've missed or maybe have a suggestion as I progress along....

 

... and WOW do I need to work on my posting abilities! LOL

Sorry, that was the first time trying to add pics into a post, didn't turn out like I had planned... and totally out of order, too!

I fail :/


and after checking it a bit further, it seems that each photo explodes into a full screen pic and plenty of detail, so I guess it's not so bad. Just the out of order thingy... jeesh!

Sorry.

 

The hardest thing with the carbs is taking them off and putting them back on. The V-four makes it pretty irritating if you don't know the tricks.

 

I've heard that the plastic tubes underneath tend to break due to their age and are irreplaceable now. That scares me the most.

 

the rubber boots...if you can afford it replace them ...the plastic tubes be very careful. do not remove the air plenum!!! unless you want to be looking for springs and finding those plastic tubes which are pretty much not available...

other than that good luck she looks good

 

Well to post the pictures ,here is a computer trick.

when in the photo file hold the control key down and select the photo's you want to place on the tableau to the posting . hope that helped..
Nice pics, as stated DON'T dismantle the intake plate use a GM carb cleans to do the work of cleaning . remove the jets and other parts. have fun and do buy new intake rubbers as it is impossible to reinstall, they cost @ $11.00 each, cheers Mike R..

 

As stated by others.....DO NOT REMOVE ,FOR THE LOVE OF GOD AND ALL THAT IS HOLY AND SACRED,THE MANIFOLD THAT HOLDS THE CARBS TOGETHER!!!!!You will have screwed the pooch if you do so. A dalmation in case you were wondering.

 

Inbetween the heavy downpours this morning I went out to the garage to try and attack the lower bands on the carb assembly, which I was able to do with a little finness. But then the damn California shit stopped me dead in my tracks. The vaccuum lines wrap around the carb like a python clinging to it's clutch of eggs! Started raining again and without the sunlight I really couldn't see too well. Gonna try again tomorrow.

So, I can remove ALL of the hoses leading to the canister as long as thats the only port they are routed to? It will clean up the look SO much.

 

yeah, most cal guys remove the canister system. It's just emissions crap.

 

You can remove all the hoses but two that are rather important, the one small hose from the tank to the charcoal canister must be left open to atmosphere and the large hose from the carbs to that goofy valve to the right rear of the carbs must be left open to atmosphere as well.The first is to vent the tank and the other is the float bowl vent.The other five can be capped, one on each carb in the center pointing at one another and the small tube on the left rear carb between the frame.

 

just one more time to be clear- DO NOT remove the plate !!!

now comes the fun- actually pulling the assembly loose. it wont be easy unless you cut the boots, which is unnecessary unless you are replacing them anyway, and then it would be easier. if others experience was anything like mine, you are not gonna believe the force required to free the beast. no amount of conventional pulling would loose the grip, and a additional application of "prying" was required for me. it was to saying the least nerve-racking, and tension filled untill it started to break free. i can do it in my sleep now, but getting them free the 1st time was no easy task. my method involves a sort of "rocking" from front to back. like the front coming up AND back and then the back coming up AND forward. one action tends to have an nearly equal and opposite reaction of the other, but eventually once you reach a certain point, you have to commit to "popping" one side loose, then the battle is won. again- others experience may differ, but for me, no amount of human strength pulling straight "up" will overcome the mounting angles involved. it will require a similar technique but less forcefull action to reverse the operation.

after the 1st time, its no big deal at all.

 

Pic of great place to pry up on the carbs to start them off.

http://vfrworld.com/forums/mechanics-garage/22449-cleaning-carbs.html#post170033

 

One trick I used that made installation a lot easier was to ditch the factory clamps on the rubber manifolds-which weren't clamping tight enough anyway, allowing air to leak past-and use narrow gauge worm gear style clamps like those found on Ducatis-at least mine...one of my other bikes. I used new rubbers, a thin layer of silicon grease on the insides, and just set the whole mess light on top of the motor...pushing down very evenly, yet forcefully, from the top...all four carbs, rubber manifolds, and cylinder head ports just came together at once. Trying to get one side started, then go to the other took forever and got me nowhere..Also, those worm gear clamps? Install them AFTER you get the carbs on, that way they don't interfere with the installation, like I found out they did on my initial attempts.

As for disassembling the carbs from the pan? It's no big deal, I don't know why people are making it up to be one at all...Just number the carbs in some fashion, like which cylinder they came from, and that's it. That's about the only way you can really do a good tear down. After a good deal of fiddling I arrived at the process as follows; complete disassembly, soak in 'carb-dip', then acetone, then a cycle or two in an ultrasonic cleaner(I used a 50/50 mixture of white vinegar and distilled water to rid the parts of some mineral deposits which the solvents didn't touch). Blow out all the passages with compressed air each time you pull the parts.

I found along the way that European spec bikes had a float level that was a bit higher than US models. I used this spec-it's in the 'hardbound' repair manual (Haynes?) with a notable difference in midrange performance. I left the jetting stock. Also, the British made 'Carb-Tune' works WAAAY better than the liquid filled manometer popularly sold here in the states.

Rick

 

You sound like you are pretty knowledgeable Rick so I'm gonna say this as respectfully as I can, There is absolutely NO reason to disassemble the carbs from the top down, removing the airbox manifold or air cleaner base as called in the schematic is just a good way to ruin old parts. The plastic tubes that run through the assembly are incredibly easy to break.This in no way helps to clean each carb in a way that will benefit the operation of the units, and could cost u anywhere from $9 to $30 to replace each piece. New rubber will definitely help in installation and future service or cleaning but PLEASE for your own sanity Lazy don't take them apart in this manner. Too much work for no real benefit (even if you don't end up ruining or losing parts)

 

When I did mine I did a leak test, turned the pump on and wiggled the fuel lines going to the carb tees, fuel sprayed everywhere so I had to dissassemble the carbs and replace o-rings on the tees. I didn't want it burning to the ground after alot of work. If you have to do it there's a o-ring place in Chandler where I got the o-rings for the fuel and vent tees. It wasn't that hard if you take your time, mine has run like a swiss watch for 3k miles since the resto. Make sure your tank is clean so you don't have to redo the carb cleaning.

Arizona Sealing Devices, Inc. - Supplier of o-rings, seals, gaskets, kits, caps & plugs plus more.

 

I actually have a pristine California cannister system if you would like to replace yours or need a spare.

 

If, perhaps you remove all the lines that lead to the carbs, and cap this particular large one, you'll end up with a bike that only runs at full choke, and stalls if you try to turn off the choke or open the throttle at all. (just figured that that out an hour ago). I'm hunting for what seems like an intermittent vacuum leak (bike idles at 1000rpm for 2 seconds, then 1500 for 2 seconds, then 1000 for two, etc.).

I'll be following this, so take lots of pics for me! I need to dig in an figure out what's up with supposed jet kit that went in when the original owner put supertrapp's and headers on it (22 years and 3 owners ago).

 

OK, update on my crazy weekend with the VFR. My buddy Josh came over (fellow student at MMI and 5 months ahead of me in classes) and we intended to get the damn carb free and clean it up, as well as hopefully be able to play around on her later in the afternoon. Well, as was the case when I was trying on my own - she wouldn't budge. So, we studied what was before us in detail, trying to figure out exactly why the carbs weren't coming free with the both of us pullin and yankin and all. The manual showed a short protrusion from the carb bottom, as well as a matching sleeve above the intake - so for the life of us we couldn't figure out why in the hell in wasn't breaking free!

We agreed that taking the filter plate off was the logical next step and might even help in removing the carbs by taking the added stress from above the carbs out of the equation. So, 8 screws later and the plate removed, we again studied the layout and moved some hoses out of the way. Then my buddy Greg shows up. That's when things got interesting....

Ya have to understand Greg, and how he thinks. He's a Marine vet, 10 yrs in the service and born & raised in Arkansas. He's a ASE certified mechanic, well he used to be... and he worked on his own Harley's when he had a bike. He's one of those fix it yourself if you've got the tools, and only take it to the shop if it's broke beyond your tools ability to fix it and you can't replace it without screwin anything else up! Bottom line, he's a wealth of knowledge and a genius at riggin things to work (I swear he took Engineering courses at some point) but he has a tendency to be extremely bullheaded and stubborn along with a bad habit of pushing you out of the way to do it right "his way".

That said, he walks in and says "What, you ladies ain't got her running yet?" Looks over what we've done and then says "You don't have to do all of this, she'd run fine if you just cleaned her out and ran the crap out of it. She'd come to life by the end of the day... trust me!" To which I explained that I wanted to do it the right way and follow it by the book so I could learn off it. He asks why we haven't got the carbs out yet and I told him the predicament we were in. He grabs a bar out of his truck and a soft hammer and less than a minute later - with the help of a bar I had - it popped out of the rubber sleeves with a loud suction sound.

2 of the 4 sleeves were split in half from the force of the removal, but it came out. What I realized later was that without the filter plate on it, the carbs were free to move in their own direction, which we noted when we pryed them up from the intakes.

Unfortunately, cause he pretty much took over at this point, I didn't get any pics of the removal or reassembly. I'll explain why.

The next 30 mins were spent disecting and cleaning the carbs. The float bowls had some residue in them, but cleaned easily. 2 of the slow jets and 2 of the main jets were clogged, and cleaned out easily. I was in the process of cleaning them out when his wife was like "We gotta go" and he just up and bails on me. He had dismantled a ton of hoses and spread the carbs apart my taking the screws out on the sides. I figured I could figure out where to go from here on my own since Josh had already left shortly after Greg showd up and took over. One of the slow jets was still not fully cleared, but at this point I was just interested in getting her back together.

The funny part: I placed the filter plate on top of the assembly and put it on top of the intakes. With one swift push, the entire assembly popped sweetly into the intakes! I nearly died in disbelief!!!! My luck was short though, cause I put some of the rings on backwards and had to remove the assembly to fix it. I had already screwed the plate back on, so the whole thing popped out very easily. After prethreading all of the rings, I tried to pop it back in and all of the sudden it wouldn't go. I mean nothing I did would get it in. I even tried a little oil smeared inside the rubber hoping it would ease the slide. Nothing. I cursed out loud at Greg and bitched about him messing me up. Then I noticed all of the hoses laying randomly on the floor that he had just ripped out when I wasn't looking and I got more pissed.

All it needed was a 16th of an inch more and it would pop inside the rear sleeves. So, I grabbed a 1 x 3 piece of scrap wood and my light hammer and started tapping at the top. We had used the wood and hammer to help get it out, so getting it back in was ok in my mind at the time. Again, no go. Several removals and screams later I decided to try pushing it more to the front. I tapped it a few times on the center lip at the top rear of the intake plate and the inevitable happened. Sweat pouring down my forehead, my temper raised, my cool way past overheated... I broke the ledge of the plate!

After a few hours of disgust and bitching myself out, I realized as I lay in bed what it was that I didn't do that made it not want to go in. 4 screws removed and it would have popped right back in place. That's it. Just loosen the plate and let the carbs seat themeselve!!! Yeah, I felt like your thinking right now.

I'm going to JB Weld the lip back on (the break was purely cosmetic in nature) and then when it's dry I'm gonna put the carb back in and get Greg to come over and help me figure out what the frack he did to my hoses! Then all I have to do is change out the plugs, new oil and filter, and fresh coolant.... then it's done!!

I'm going to post pics of the break and the cleaned carbs in the morning. It's big difference, and I'm hoping that it runs smoother after it's done. By the end of the week I should be riding her

 

starts feeling queezy

feeling intensifies

dude, i hope it is as you say only "cosmetic" and you are up and running soon

if you need help with the hoses, i have the manual, and can snap some pics for you

 

You're a student?

So far you've earned a D on this project cuz you broke something, refused to listen to your instructors, and received "help" from unauthorized persons.