Strange gear/clutch effect

[Maciejewski]

Hi Guys. I was looking to buy a XB9 Firebolt from 2003. The bike starts well, idles and revs pretty ok. Problem starts when ridden for a few minutes. After shifting to 2nd or 3rd (basically any higher gear) the gear gets engaged, but after a split second I get a feeling as the clutch would start slipping (on acceleration) just for a few seconds, as if you were trying to do a wheelie, and then it catches on again very rapidly. There is a rattling sound that goes with this. Has anyone came across anything like it? Any input much appreciated, thanks!

 

[34nineteen]

Hi Guys. I was looking to buy a XB9 Firebolt from 2003. The bike starts well, idles and revs pretty ok. Problem starts when ridden for a few minutes. After shifting to 2nd or 3rd (basically any higher gear) the gear gets engaged, but after a split second I get a feeling as the clutch would start slipping (on acceleration) just for a few seconds, as if you were trying to do a wheelie, and then it catches on again very rapidly. There is a rattling sound that goes with this. Has anyone came across anything like it? Any input much appreciated, thanks!

Could be the spring plate in the clutch pack coming apart. Doubt its the dogs slipping, but I guess that could be a possibility.

Or it could be the crank pulley bolt has loosened off the crank and the rotor is coming off the splines.

 

[Maciejewski]

Thanks a lot bud, will have a look at that :up:

 

[Cooter]

Only on super hard acceleration? Or can you ride it normally?

Even though your description sounds like dogs chattering and slipping, each set of gears has its own set of dogs, so it's unlikely they are ALL worn badly enough to skip.

A shift fork will typically bend back (the direction of force) and then wouldn't allow the dogs to seat in different gears but it's super rare though. A worn shift drum (even more rare) would do the same.

I'd dive into the primary where all the magic happens, check the crank pulley like Fred Sanford said above, and pull the clutch to inspect the basket and nut as well. Take a gander at the output pulley too. You'll have telltale shavings and terribly wobbly things if splines are shot enough to slip.

Either way its a hard pass no matter how cheap it is, unless you're a mechanic. Transmission repairs require removing the engine and splitting the case.

 

[Maciejewski]

Thank you kindly, that’s a lot of information very professionally given, Guys. I will have a look at what is easily accessible, but I guess taking the engine out and splitting might not be the best way to start with a new bike

 

[Maciejewski]

This would be on even very slight acceleration.

 

[Barrett]

You need to discern the difference between a gear not properly engaging...and a failing clutch pack assembly and/or its ancillary components. Takes substantial experience and a keen ear to differentiate between what's possibly amiss inside the engine case, or failing inside the primary cover. In all likelihood, what you're describing is a problem residing under the primary cover, circled in yellow. A few specific dedicated tools and more than a modicum of wrenching abilities required to address and repair same, which I doubt you possess. Have an available XB/XL/XR tech in your area willing to assist? Then consider purchasing for very cheap money. If not, walk away.

 

[34nineteen]

To wit, you're probably going to be in for a clutch pack at least, and possible transmission replacement at most. To help narrow that down, you will need to remove the primary like Barrett illustrated, which you likely will not be able to do pre-purchase.

Unless you're getting it really really cheap ($1000), and dont mind spending hours doing a job that should take 30 minutes, I'd walk away from it. The other reality is that all of the XB's are now 10+ years old and some getting ready to hit the 20 year mark (like the early 2003 models), so you are going to have to be ready to work on it. Most of the XB's I've bought have had owners who just put gas in and rode them until they stopped running. No matter how simple or cheap the seller claims the repair is, just bear in mind, if that was really the problem or it was really that cheap to fix, they would have already done it.

The later bikes, especially the 08+up models are the better of the lot, and while they dont make more power, they are more refined and have longevity upgrades already done. They do command more $$$ but they are worth every penny for a well cared for example (like Barrett's bikes).

 

[Cooter]

I would pay $1000 for a NICE Buell with clutch problems, I might not take a free one with trans issues. Sure, call me trans-phobic:upset:

OP's description is pretty vague but it's the:

and then it catches on again very rapidly. There is a rattling sound that goes with this.

that makes me think bad things like gear dogs or splines, not just a slipping clutch.

Are you shopping for a Buell? Get a good one. You'll love it.

Or are you just shopping for a cheap bike? Go Japanese.:upset:

 

[34nineteen]

I would pay $1000 for a NICE Buell with clutch problems, I might not take a free one with trans issues. Sure, call me trans-phobic:upset:

OP's description is pretty vague but it's the:

that makes me think bad things like gear dogs or splines, not just a slipping clutch.

Are you shopping for a Buell? Get a good one. You'll love it.

Or are you just shopping for a cheap bike? Go Japanese.:upset:

Youre a cheap bike.


The answer should reveal itself once the primary cover is off. It could be something simple as the grenade plate coming apart slowly, however good luck getting the seller to let you pull the cover to determine that.

It would be really weird for multiple gears to have bad dogs unless the bike has been hammered on.

 

[Cooter]

You're hammered on.

 

[Maciejewski]

You need to discern the difference between a gear not properly engaging...and a failing clutch pack assembly and/or its ancillary components. Takes substantial experience and a keen ear to differentiate between what's possibly amiss inside the engine case, or failing inside the primary cover. In all likelihood, what you're describing is a problem residing under the primary cover, circled in yellow. A few specific dedicated tools and more than a modicum of wrenching abilities required to address and repair same, which I doubt you possess. Have an available XB/XL/XR tech in your area willing to assist? Then consider purchasing for very cheap money. If not, walk away.

View attachment 16049

Thanks Barret, you might be right saying to walk away. I will see if there's anything I can do. Appreciate your comment.

 

[Barrett]

My pleasure Sir. This October, the XB9R you're considering will be 20 years old. Any bike in that age range is going to need both attention to detail and specific maintenance to bring it back to "like new" standards. Couple that with the fact that all 2003 XB's had a few teething problems....smaller spec drive-belt....side stand and side stand safety switch and front brake hose defects sufficient enough to warrant factory issued TSB's to all dealerships....if I were you I'd continue your search.

 

[Maciejewski]

My pleasure Sir. This October, the XB9R you're considering will be 20 years old. Any bike in that age range is going to need both attention to detail and specific maintenance to bring it back to "like new" standards. Couple that with the fact that all 2003 XB's had a few teething problems....smaller spec drive-belt....side stand and side stand safety switch and front brake hose defects sufficient enough to warrant factory issued TSB's to all dealerships....if I were you I'd continue your search.

That's valuable information and a good point. Cheers Bud!

 

[MOTORCYCLES247]

Not sure if you are still working on your problem but I have pictures of BOTH STYLES OF TRANSMISSION for the XB's 03-05 which are Straight Cut gears and 06 an up are all Helical Cut also 3 of the 4 bearings are different size in the 06 and up transmission. Just to point out the first picture is 03-05 XB trans and the second picture is the Shift Drum from the 03-05 trans with the bad shift fork channel-second row up has a worn corner on the high point of that channel. 3rd picture is the 06 and up trans which is what I went to along with 06 and up ENGINE CASES which I got off E BAY for $ 99.00 plus shipping.

 

[34nineteen]

Did the new transmission require a new case? It seems like the complete transmission would retrofit into either case. I think the only difference between early and late cases was the extra threaded hole cast into the RH side by the belt pulley for attaching the oil hoses. Or at least thats all I noticed.

 

[MOTORCYCLES247]

YES YES YES the 3 bearing size difference is the outer diameter mostly and the biggest one of all is the output shaft which is a double row bearing in the 2006 and up unlike the single row bearing on the 03 to 05 years. The engine case I was able to buy was from 06 and the transmission was from a 07 which they destroyed the output shaft bearing removing it which coast me $ 56.00. All together I was able to get rid of the repeat failing ALL ALUMINUM SHIFT CAM with the better all steal shift cam version of the 06 and newer engine cases and 07 trans all for under $420.00 . Cases for 99 plus shipping and 175.00 for the trans. Output bearing 56.00. I have 14,000 ish on the new upgrade until my now not running well issue. View attachment 1

 

[MOTORCYCLES247]

YES YES YES the 3 bearing size difference is the outer diameter mostly and the biggest one of all is the output shaft which is a double row bearing in the 2006 and up unlike the single row bearing on the 03 to 05 years. The engine case I was able to buy was from 06 and the transmission was from a 07 which they destroyed the output shaft bearing removing it which coast me $ 56.00. All together I was able to get rid of the repeat failing ALL ALUMINUM SHIFT CAM with the better all steal shift cam version of the 06 and newer engine cases and 07 trans all for under $420.00 . Cases for 99 plus shipping and 175.00 for the trans. Output bearing 56.00. I have 14,000 ish on the new upgrade until my now not running well issue. View attachment 16096View attachment 16097View attachment 16098

 

[34nineteen]

Interesting. I didnt bother to take measurements of those bores, but now I'm curious. Not that I dont believe you....

 

[MOTORCYCLES247]

The picture of the two smaller bearings are for the place on the lower counter shaft the left bearing is the 06 and up size and the right was my old 04 which is the 03 -05 year size. Plus the right side bearing is thicker. Just one of 3 that are different in O D size. Only the counter shaft needle bearing was the same size. The main shaft output bearing is completely different and so is the SEAL. I was amassed that I was able to find perfectly good cases even after shipping and also the trans for so little.