Just spent the last three days out at Glamis and had some occurances that I've not experienced before. Let me throw this out first, I pulled up every thread covering clutch slippage and don't know if that's what I'm getting or not. I did change the oil before I left, GN4 like I've used since day one, proper levels and all, nothing done differently since the last dune trip (Dumont) at all.
Saturday AM we were out cruising and it started getting very hard to shift up, seemed like the shift lever would stick. Went back to camp and let it cool down, went back out and seemed to be running fine the rest of the day. Sunday and Monday I started noticing that while duning, didn't have the problem while hill climbing, seemed to only be in fifth, that at higher rpms it felt like the wheels were breaking loose and really spinning. Started looking and no roost was occuring during this, just the huge increase in rpms.
So my question is, does clutch slippage only occur in forth or fifth gear? Seems like it would be across the board if that's what it is. Did not notice it at all in 1st through 3rd and don't believe it happened in 4th.
This is on my 03 with BigGun exhaust, K&N, jetted, 22" Sand Stars, 15t front, some of oldmanracings stock carb mods, never a day of problems before.
Seemed to me the sand at Glamis was much heavier than at Dumont so this may have contributed. Normally do open desert and trail riding so it might have taken Glamis to really tax the system.
If you need more info than provided I've got it right here.

Anyway, I have to get this fixed in time for MLK, so I'm all ears boys. Let 'er roll.

Oh Yeah, after ths started I noticed that when I shifted up after a few seconds in gear the shift lever would seem to slap down into my boot. No high revving or anything before this would happen, just business as usual then the lever dropped down. Every gear, except 1st. Don't think I ever used first the whole time.

 

It's time for clutch springs!!! and maybe a clutch. They get weak after awhile. Plus any new found power will really make it hard on the stock ones.


Stock fibers with either,
RW's 60%
Pami's
or complet
Barnett clutch 8 or 9 dis with springs.

Take your choice!!! [img]i/expressions/face-icon-small-smile.gif[/img]

 

GN4 is a dino oil so I doubt that it is causing you any issues.

It sounds like you definitely have some clutch slipping issues. I can't answer why you didn't notice it 1st through 3rd, but what you describe sounds like it is slipping. I would hate to think that the odd shifting problems are related to the transmission, I hope they are just complications of a worn clutch.

If it were me, I would pull the clutch cover and inspect the clutch. Are you currently running a stock clutch and springs? You may be due for a new clutch, why not add some stiffer springs too or go for the 9 disk setup.

 

Only thing I've ever had any part of the case open for was to put in a new oil filter.

So then, it sounds like what the other threads were talking about. Now I need some 60% stiffer springs and at the least to do the sanding job on the plates correct? For my riding style would I need to go with the Barnett 9 disc kit and what are the advantages and disadvantages of them? I don't do alot of serious hill shooting/racing but do like to cruise the dunes with my kids and friends for hours at a time.
It looks like others aren't impressed with the Barnett springs and go with other makes even with thier plate package. Am I understanding this right?

Sounds like I'm going to learn what's involved with tearing into the engine.
Thanks so far gents.

 

The leverage of the higher gears works against the clutch plates. Take a bicycle. In the lower gears you have to pedal faster to move at a given speed but there is much less pedal resistance. The higher gears have much more pedal resistance. Same with the clutch. The reason the motor spins up faster in the lower gears is because there is much less resistance against what the motor is trying to do. Less resistance against the motor means less demand of the clutch.

It is natural for a clutch to start slipping in the higher gears first IMHO.

I don't think any stock clutch has long to live on sand. Paddle tires, horsepower robbing turf........ lots and lots of resistance and demand on the clutch. I would get a 9-disc clutch system like Barnett or HPR. Stiffer springs can help but they are not the answer. What you need is more surface area and additional clutch plates give you that. At bare minimum, now that the clutch as slipped, if you go the stiffer springs route, resurface the metal plates. Oldmanracing has a protocol for this that he sends everyone with clutch slippage. It shouldn't be hard to find.

Ron

 

I haven't had to do a clutch yet but this might be the info from Oldmanracing on how to sand the discs.


Wed November 30, 2005 6:56 AM



It is time to refinish the steel plates.
The crosshatch on the plates has been polished off and now the fiber dics have no surface to bite into. If you do not refinish the steel plates the fibers will gloss up and then are junk.
The crosshatch adds bite and allows oil to wring out so the plates run cooler.
Oil is trapped between fiber and steel plates. If oil cannot get out plates will overheat and gloss the fibers.

Some quidelines:
Use 300-320 sandpaper(black wet/dry)
Cut a strip 3x8
Tape to peice of glass for flatness or flat countertop - length away from you
Lay disk on paper with paper going threw center of disk at 12 and 6 o'clock
Pull towards yourself 2 times
Rotate width of paper and continue till crosshatch is across all of disk
Turnover and do opposite side as above.



Good luck and let us know how it comes out.

 

" does clutch slippage on occur in forth or fifth gear? "

Its usually occurs there.

 

Okay, now that I've had a nap, and a little EggNog and E&J, I seemed to have coaxed some memory cells back into action.
I also had a few occasions where we would stop and I'd put my bike into neutral, then I would hear what sounded like the gears not fully disengaged, then they'd drop into gear, lurch and obviously die. I'm hoping this is also from the clutch plates needing replaced?

On a side note, I mostly ride at 2000-2200 elevation. When we go to Dumont both DS's seem to run fine with no adjustments. Down at Glamis I noticed when both bikes were shut down I would get a very muffled, slight backfire. Not every time but on most occasions. Do you guys that live at higher elevation adjust the air/fuel screw for Glamis? The idle seemed to be fine.

The spring question really hasn't been answered yet...

So, per oldmanracings guidance in other threads, I need to take the shine off of the steel plates. Is this whether or not I go with aftermarket friction plates or only if I leave the OEM as they are? I would venture to guess that it should be done in either instance.

 

clutch wear or weak springs do not make for hard shifting, or shifting issues. sounds like you have two different issues to me. shifting problems like you describe have led to the discovery of a couple different things in the past - the actuator gear that acts on the pressure plate is plastic and has sometimes lost teeth, easy and cheap fix and you can inspect it while the cover is off for the clutch replacement. also problems with shifting forks, which can only be fixed by case splitting. not trying to alarm or anthing, perhaps a little is lost in translation, I would install a new clutch and inspect the actuator gears as described, then ride and see how it all jives. If you then still have the problem of hard shifting and popping out of gears then do more research on shifting forks.

But as far as clutch wear and springs go, they go hand in had. Any upgrade to the DS at all requires the installation of stiffer clutch springs to preserve clutch life. Adding power will cause clutch slip - only minor slip that often goes unoticed, like between shifts when dragging in the sand, especially if you power shift - and the result of this slip is fiber wear. So what you need is new fibers, and also heavy springs to make the new fibers last longer. Whether or not your steel plates need replaced or sanded can be determined upon disassembly. Sometimes steel plates can become warped from excessive heat from major slipping. if this is the case, they are trash and should be replaced too.

 

Once your clutch slips, your fiber plates will glaze up and the steel plates will get polished. If you pull your plates, spec them out to make sure they are within thickness limits and are not warped, and you decide you want to put them back in the quad then follow OldMans instructions as to how to resurface the plates.

Unless your plates are almost brand new or you are on a very tight budget and have time to spare, I wouldn't hassle with resurfacing the existing plates. My theory is once I am in there with the clutch cover off, I want it to last as long as it can, which it won't if you put 1/2 worn used plates back in.

If you decide to go with the stock plates, then I would suggest some stiffer springs. The barnett 9 disk does come with its own springs, but they are very soft, maybe even softer then the stock springs. I run the barnett 9 disk along with RWR 60% springs, no problem and the pull is light with my hydro clutch.