FD slippage???

[Lbrown311]

I was noticing some slippage at high RPM's recently. Today I took a turn and tried to hit her in second....sounded like a clunk in the FD. Felt it in the seat. Anyone have an idea what this is. Am I having the classic 2nd gear issue all of a sudden? It has slipped in other gears, but that was the first time I actually felt it clunk. Any help would be great. Thanks in advance.

[DGXSER]

This is a classic symptom of the gear slippage issue. It is just starting in my opinion, as in the gears are just getting to the point of slipping.

You may want to try upgrading your clutch springs. On my bikes I have found that when I take the clutch apart and measure everything, only the springs tend to be out of spec. replace those with HD springs and no more clutch issues. But that won't solve your gear slippage. I think most of what you have been feeling may be clutch slippage, and now your getting into gear issues.

[BA80]

If it's just slipping a little now is the time to dremmel the gears and do the washer swap on second. If it just slips once in a while in second the washer swap might take care of it all together.

But if you pull the gear shaft you might as well touch up the dogs on those gears anyway.

[TopCatGr58]

Hey Brown,

Well, the terms "gear slippage" is a bit of a misnomer, it should be gear JUMPING..cause that's more like what it feels when the gears "slip" their engagement, and then SKIP past each others dogs/slots until they re-engage.

With regards to the clutch and the high rpms, that's more appropriately called SLIPPAGE, because it's a smoother action, where the rpms rise, but the bike speed/mph doesn't ! As stated, stronger newer springs are the most common way of fixing it, provided you've already done the proper clutch tension adjustment at the engine first. You'll have to take apart the clutch to get into the engine for the dremmel fix, so it's a good time to replace the springs, as well as measure/micrometer the frictions to ensure that they are within spec, or replace if out....less than 2.8mm thick, vs. 3.0mm max thickness. Also clean up the steels as well. See the tech tips, both the dremmel fix, as well as the extra steel plate....even though you may not necessarily need to put in the extra steel, still lots of good photos and tips/techniques for doing the job.

T.C.

[Lbrown311]

well what I was feeling before was slippage at high RPM's and now today, I got my first clunk and it was in 2nd....(or so I belive). I am using 10w 40 oil which I think has something to do with it, because when I was using Mobil1 15w 50 I never felt it. The clunk scared me a bit due to the fact that it was for sure gears missing and then reconnecting. My bike only has 27k on it, so I don't wanna over think it quite yet. I will check some smaller problem areas first and then dig into the tranny. I wanna check the simple things since I've redone the bike to ensure there has been no mishaps there first. My slippage might have been in 3rd gear. I am still an amateur rider....sooo I need to assess the situation a little more. I always ask for opinions first tho before I assess the bike. Seems I get a waaaaayyyyy better idea of what I'm looking for. So thanks for the tips. Look forward to more. I will keep you updated.

[jetmechmarty]

Your switch in oil viscosity has nothing to do with this. What kind of oil are you using? If you're using 10W40 from off the shelf that was designed for the family car, you are inducing a slipping clutch. Use motorcycle specific oil or Rotella T or something similar.

As a side note, W40 is the correct oil for your bike. When you use thicker oil, you will gain heat. (I don't believe W50 will hurt anything.)

[Bonz]

10W40 is not the issue either... There isn't one 10w-40 family car oil out there that has the "friction modifiers" you are referring to. Anything in the ?w-30 range will have the stuff we don't want in our engines, but nothing in 10W-40 and higher ranges does to my knowledge, regardless of whether it's a family car oil or not.

[motoman]

Having previously synthetic in it and changing to presumably non synthetic may be causing the clutch pac to slip a bit. Change it out and filter for some 20-50w of your choice(non-syn.), ride it a bit and see if that doesn't correct the problem....JAT....

[Bonz]

I had always heard going TO synthetic has been reported to cause slipping, but I've never had that issue. Hadn't heard going form synthetic TO dino (actually not dinosaurs, but long-dead sea plankton makes up our oil supply) had been known to cause slipping when initially making the transition.

Learn something every day hanging out with you guys!