How to fix a "Dragging" 86 VF500 Clutch

Hey guys,

This post is a follow up without the heavy reading to this thread I posted a few weeks ago:
http://vfrworld.com/forums/showthread.php/48999-86-VF500-Clutch-issues

You've all been extremely helpful to me as I've worked for the better part of the summer to resurrect this 86 VF500 which I bought for $700 CAD in May.

I'd like to take this opportunity to talk about troubleshooting a dragging clutch (ie. pulling the clutch lever all the way doesn't totally remove the force on the back wheel and makes shifting while stationary almost impossible).

Some things I learned with the help of the internet, other members of this forum, the service manual and my dad helped me troubleshoot this and I'm running great now.

1) Make sure your bike likes the oil that's in it. I'm not going to get into an oil debate, I'm just going to say that shell rotella T 15W-40 diesel oil works very well for me. The root of my issues as it turned out was an expensive synthetic oil which I thought I was doing a good thing by putting in but it had friction modifiers and was heavier than I probably should've used. As I've discovered, in a wet clutch (which we have) the type of oil will have profound impact on clutch performance.

2) Properly bleed your hydraulic clutch system, Squirrelman gave me a great technique for that in the thread I've linked to above. It involves removing the slave cylinder, using a clamp to keep it retracted and then pumping the handle so you don't just push air around, you push it out of the system.


3) Check the steels for warping, that probably should be one of the things you check before pulling off the stator cover as you can change them without removing the clutch basket.

4) If the bike has been sitting for a long time the plates could just be stuck together and will require a little encouragement to come apart, they may need replacing.

5) if anyone was confused about the judder spring shown in the service manual:



Be aware you can run without one and that last friction plate with the wider ID. You can replace them with a standard friction plate and you'll have a slightly grabbier but fully operational clutch. Conversely, I've heard removal of a judder and replacement with another proper friction disk is a solution to some slip problems.


6) Worn clutch basket/hub: your clutch basket caddies your friction plates while the hub holds the steels. Under prolonged use or short term abuse the friction disks and/ or steels will bite into the basket/hub creating grooves. These grooves are obviously created when the clutch is engaged and then even when the clutch is opened, the plates are inclined to stay in those grooves and not seperate (causing the dragging). You may need to remove the basket/hub and file the grooves off or replace the worn part if you can get your hands on one in better condition. NOTE: If you decide to file a clutch basket, use a draw filing method. This means using the file 90 degrees to the direction you would normally push a file and push down the fingers of the basket instead of across them. This way the striations run the same direction as the plates should slide. PROTIP rub soapstone or chalk into your file first, trust me, the results justify it and it's easier on your file.

This IS NOT a vf500 clutch basket but same idea:

7) If/when you do have to remove the basket from the bike, you'll need to remove both the right crankcase cover and the stator cover on the left side. (obviously after draining the oil). You need to use a special tool and a friend to get the starter clutch off before the basket. You'll understand immediately why when you get in there and you realise the stator will just spin when you're trying to loosen the bolt on the starter clutch.

I made this simple tool to hold the stator. Measure your own stator before making it but mine was 72mm from hole center to hole center with a little over 9mm diameter holes. I drilled a bar of aluminum with 1/4" holes and put 1/4"-20 allen bolts through it. The heads of the allen bolts just perfectly fit into the grip holes of the stator. Here's what it looked like:




8) The nut on the clutch basket/hub can be removed while your friend stomps on the rear brake although ideally you have the special clutch hub holding tool which can be seen in the factory service manual or purchased on ebay for about $20 USD

9) When reinstalling the clutch basket it is SO EASY to mess up how it is seated. There is an oil pump drive sprocket behind it on the same spindle. It has little nubs which need to mesh with the little nubs on the back side of the clutch basket. You will need to make this fit completely blindly because you can't actually see much but the primary drive gear (big gear behind the starter clutch) and the big gear attached to the basket will sit flush. If your basket gear appears to be meshing with the primary drive but is still sitting about 1/8" further out than the primary drive, you haven't seated that oil pump sprocket properly yet. It really is a pain but absolutely mandatory, otherwise a few nasty things happen (as I learned the hard way). First, the starter clutch gear will ride the clutch basket and you'll find shredded aluminum in your engine and oil plus damage to both components. Second you'll find the hub binds to the inside of the basket and behaves like an always completely engaged clutch. Third, your oil pump is not engages and therefore your engine and clutch get no oil!


And just cause you guys like pictures, here's my fully operational and road ready machine!

 

Thanks for taking the time to write that. I am sure it will be useful to many in the future.

 

My pleasure, I hope it helps some poor guy (or girl) in the future.. wasted two weekends of summer trying to sort it out :blue: If I had known then what is in this thread it would've taken me 4 hours
:chaingun:

another great resource which helps diagnose other issues with our clutches is here: http://www.motorcyclecruiser.com/tips-tech/how-to-ins-and-outs-clutches

 

I have issues with changing gears up and down within my '84 VF500. Often it is hard to change, when possible at all. Not only change to another gear is an issue, but it is very hard and it starts to hurt when I'm trying often to change gear. Within my VFR I can change gears by only using my big toe, but my VF I need to use the middle of my foot. Second, I have replaced the engine about a year ago and I've read your previous post as well. Things done so far:

1) When the new engine was placed I've put new part-synthetic oil, specific for motorbikes at a local store here in my town.
2) IMO I have drained the clutch well, but need to have a second look as I am reading this article.
3) Last time I checked the steels was about a year ago, before placing the new engine. As far as I can remember the steels weren't worn.
4) Concerns me a bit, because in between I went half year abroad and in the winter I haven't start my bike. So the engine stood still for about a year.
5) Not relevant, see 3)
6) See 5)
7) See 6)
8) See 7)
9) IMO I've done a proper job. As an engineer, together with a mechanic friend we've assembled the clutch the good way. But because I've checked every part inside over a year ago it makes me doubt

I have changed the clutch reservoir on the steering bar, because it was leaking after revision. I was able to adjust it a bit with the adjustment screw. I've noticed that changing the gears went better when the screw was turned until the end. Therefore the bike first started rolling when I let go the lever until 2/3, which isn't good as well. Are there maybe other possible causes for not changing into gear? Or should I worry about 9)? Thanks a lot in advance!