Clutch slips when cold out but not warm?

[6pak]

Has anybody had a problem similar to this? I took about a 90 mile ride yesterday. the operating temp for the bike never got more than about 1/4 inch above the cold mark on the guage. If I got on the throttle hard the clutch would slip. It was fine under normal conditions. It has never slipped when op temp was up in normal range. (about halfway). Nor does it slip at higher temps. Is this something new developing with my clutch or just an oddity of the brand?

[Yammer Dan]

Letting you know of things to come.

 

Change fluid?

 

Change springs?

 

Change clutch?

[Squidley]

Letting you know of things to come.

 

Change fluid?

 

Change springs?

 

Change clutch?

 

 

 

When was the last Fluid Change?

[5bikes]

Went out Sat. on Venture, never got over 45F. outside. My oil temp gauge never got above 130F. Same for my oil cooled Suzuki(s). My conclusion: Thick oil between to the clutch plates not allowing them to mesh properly, come together. Oil is best around 160-175F. New clutch springs would help too. Don't use oil with anti-friction additives ie.

(synthetics:mo money:). I use dino oil (cheapest I can buy) get 100+k miles out of all engines with no leaks, no burning, no slipping....

[Yammer Dan]

Letting you know of things to come.

 

Change fluid?

 

Change springs?

 

Change clutch?

 

 

Joe what I ment to say was this is about the order you need to do to check it out. Hadn't had coffee yet!! Sometimes fluid will do it and it don't hurt nothing to change it out anyway. If that don't work a new set of springs will cure most of them. The clutch it self will hardley ever wear out. But there are some tricks to do to it if this don't cure it. Let us know as you go thru it. And it could have been the cold oil but I don't think so.

[RandyR]

what kind and weight of oil?

[frankd]

My 83 has had the same problem for a couple of years. Before I gave it to my brother last year, I put a complete low mileage used clutch assembly in with brand new springs. I de-glazed the metal plates, replaced the clutch basket and everything else off the low mileage clutch. It got a little better, but not much. Now my brother says it's gotten worse. My thoughts are to shim the clutch springs (it's an 83 with the conventional springs--not the diaphram sprng like the 89) or replace the clutch cylinder. The clutch fluid has been several times over the years. Any other ideas??

 

Frank

[6pak]

Ok, fluid was changed this summer. I am going to scuff plates and put in a heavier spring. I'll let ya'll know what that does.

[ctraylor]

I had the same problem with my 86. I was using Castrol 20W50 car oil and mine started slipping. I changed to Rotella and after about 3 oil changes the slip was gone. The type of oil makes a great difference. I am sold on the Rotella oil now.

[warthogcrewchief]

Something I haven't seen mentioned yet is a brake fluid (for clutch side) change and a bleed. I wonder if it could be slipping because the clutch is not fully engaging due to old fluid or air in the system.

[Yammer Dan]

That can happen. On the 83-85's with the individule springs I have had luck with adding a washer to each spring. Tightens them up a little and No Slip!! But this a tempory cure. New springs will last a lot longer. And replacing the 1/2 plate in there with a full one helps but I can't remember how. Hey Squid Where are you???

[Big Daddy]

My 83 has had the same problem for a couple of years. Before I gave it to my brother last year, I put a complete low mileage used clutch assembly in with brand new springs. I de-glazed the metal plates, replaced the clutch basket and everything else off the low mileage clutch. It got a little better, but not much. Now my brother says it's gotten worse. My thoughts are to shim the clutch springs (it's an 83 with the conventional springs--not the diaphram sprng like the 89) or replace the clutch cylinder. The clutch fluid has been several times over the years. Any other ideas??

 

Frank

Barnett sold me a set of springs for my 83 from a 57 Sportster (thier recomendation) that and new friction discs and it never slips now! A little more effort at the lever but it never bothers me.

[Condor]

I have a ton of info for a clutch that slips when hot, but this one has me stumped??? Slipping when cold and locking up when hot is something new. I'm wondering?? if the slave might be a bit gunked up or rusted internally, and the piston cup is keeping the springs from fully returning the push rods until things start to heat up???

[friesman]

This is exactly what my 85 was doing before the rebuild last year. When the bike was cold i could roll on throttle in any gear and it would slip, after warm up it would be fine. I told Rocket about this so he replaced the springs in the clutch with the Barnett springs.

My clutch hasnt slipped since but the clutch lever did get a bit harder to pull.

 

Brian

[gscbertrand]

I was told by a rep. from Penzoil that motorcycle oil had additives to handle the clutch and transmission, and also make sure its the correct weight for your bike. Mine takes 20w40

[Dano]

Slipping when cold and locking up when hot is something new. I'm wondering?? if the slave might be a bit gunked up or rusted internally, and the piston cup is keeping the springs from fully returning the push rods until things start to heat up???

 

 

I think you're on the right track Jack, it has to be something in the pushrod route and function that is causing this. Either it is the cup which is not returning, the oil seal at the left side of the case could be getting hard and not allowing full retraction of the rod when cold, gunk behind the cup from the hydraulic fluid or the piston cup could be pitted and catching on the slave cylinder. Might as well pull the slave cylinder, pull out the long rod from the left side of the case (tricky, but can be done), pull the short rod from the clutch side and check all pieces. Roll the long rod on a flat piece of glass or steel to check for warpage (might not be much), change the fluid and reassemble.

 

As far as the full plate at the back of the clutch pack, remove the plates and friction discs, remove the small spring wire around the outside, remove the half plate and replace with a full disc. You don't need to re-install the spring wire, restack your plates (hopefully you kept them in order) make sure to match up the notches properly with the clutch boss cage. (Do I got that right fellas?!)

[Yammer Dan]

I think you're on the right track Jack, it has to be something in the pushrod route and function that is causing this. Either it is the cup which is not returning, the oil seal at the left side of the case could be getting hard and not allowing full retraction of the rod when cold, gunk behind the cup from the hydraulic fluid or the piston cup could be pitted and catching on the slave cylinder. Might as well pull the slave cylinder, pull out the long rod from the left side of the case (tricky, but can be done), pull the short rod from the clutch side and check all pieces. Roll the long rod on a flat piece of glass or steel to check for warpage (might not be much), change the fluid and reassemble.

 

As far as the full plate at the back of the clutch pack, remove the plates and friction discs, remove the small spring wire around the outside, remove the half plate and replace with a full disc. You don't need to re-install the spring wire, restack your plates (hopefully you kept them in order) make sure to match up the notches properly with the clutch boss cage. (Do I got that right fellas?!)

 

 

Sounds right to me but I have done it wrong. Just make sure you put them back the same way they came out.

[Squeeze]

I think you're on the right track Jack, it has to be something in the pushrod route and function that is causing this. Either it is the cup which is not returning, the oil seal at the left side of the case could be getting hard and not allowing full retraction of the rod when cold, gunk behind the cup from the hydraulic fluid or the piston cup could be pitted and catching on the slave cylinder. Might as well pull the slave cylinder, pull out the long rod from the left side of the case (tricky, but can be done), pull the short rod from the clutch side and check all pieces. Roll the long rod on a flat piece of glass or steel to check for warpage (might not be much), change the fluid and reassemble.

 

As far as the full plate at the back of the clutch pack, remove the plates and friction discs, remove the small spring wire around the outside, remove the half plate and replace with a full disc. You don't need to re-install the spring wire, restack your plates (hopefully you kept them in order) make sure to match up the notches properly with the clutch boss cage. (Do I got that right fellas?!)

 

Exactly !!

[Condor]

If there's a need to pull the rods it can be done using one of those slim pencil magnets that extend like an antenna. Also be very carefull not to loose the ball that fits between the short and long rod. Also be carefull that when reinstalling the rods to make sure that rod ends, that have a slight flat surface, go against the ball. Otherwise the ball will want to slip off the rounded tip and cause binding.

[Venturous Randy]

On my 83 I went with sparkplug washers until I could rebuild it with heavier springs and new plates, which measured the same thickness as the old. It is my understanding that on the MKII's you can double up on the diaphragm spring. The reason I state this is I have a diaphragm spring I ran across yesterday that I was going to throw away, but if anyone wants it, let me know and I will send it to you.

RandyA