2002 LeMans Shifter Pawl Spring

[Jim Malm]

First, apologies for staring a new thread on this, but I was afraid my question would be lost in the plethora of replies to my original post on the subject. I got my new aftermarket spring yesterday and I went out to the dealer where my bike current resides, Westside Motorsports, to get my shifter pawl. I was provided the whole intact sideplate which I carefully dissassembled. I was prepared to start filing on the pawl boss to make the spring fit properly. Before commencing filing work on the boss I measured it and found that it was 16mm in diameter. I fitted the new spring on the boss and found that it fit loosely on the boss. It measured 17.03mm. I then tried the broken spring and found that it also fit loosely and measured 16.90 mm. Having read the info in FAQ, I was under the impression that the spring would be a tight fit on the boss and cause drag - not the apparent case. What I did find that was mentioned in FAQ was a rough area on the pawl mechaism where the short end of the spring rests. There was also a bright gouge where it had dug into the metal there. There's a very nice photo of that condition posted in FAQ.

 

From what I found it doesn't appear that any work is need on the pawl boss as the new spring seems to fit without any drag. I plan on just smoothing out the area where the spring rides on the pawl mechanism so that it is provided the opportunity for better movement and then just putting it back together. Am I missing anything here? It looks like someone figured out that making the spring hole bigger could solve the problem. Has anyone else doiscovered this situation? Thanks!

 

Jim

[Baldini]

Jim,

 

Have you tried operating the shift mechanism with spring in place?

 

Tho it may be a loose fit at rest, when shift mechanism operates, the spring tightens up around the oversize boss to the point of binding. This stresses the spring until it eventually snaps at the weakest point (the sharp 90deg bend). The boss on the pawl arm should be 15mm (from memory). The spring should not bind on it when operated at extremes of travel.

 

KB

[belfastguzzi]

From what I found it doesn't appear that any work is need on the pawl boss as the new spring seems to fit without any drag.  I plan on just smoothing out the area where the spring rides on the pawl mechanism so that it is provided the opportunity for better movement and then just putting it back together.  Am I missing anything here?  It looks like someone figured out that making the spring hole bigger could solve the problem.  Has anyone else doiscovered this situation?  Thanks!

Jim

61494[/snapback]

 

Exactly what Baldini says – the spring will sit loose, but when it operates, then the coil tightens and binds on the boss. You can work it by hand and see that. It may not look like a big deal, but clearly it is, as it's enough to stress the spring to the degree that it causes it to break. So file away until the spring doesn't bind – around 15mm. You gave the sizes of the spring coils: I can't remember what size the 'new' bigger coil spring is, bit it must be in the FAQ somewhere. If you have the big coil, you don't need to do any work, supposedly. It's still worth checking the operation and tailoring your set-up as needs be.

 

But what do you mean by 'making the spring hole bigger'?

If you mean the area where the spring-end hook sits. I made an indentation for it to sit in primarily to compensate for the shorter spring length, as I was using my broken spring that I had 'repaired'. Or do you mean something else?

[Jim Malm]

Exactly what Baldini says – the spring will sit loose, but when it operates, then the coil tightens and binds on the boss. You can work it by hand and see that. It may not look like a big deal, but clearly it is, as it's enough to stress the spring to the degree that it causes it to break. So file away until the spring doesn't bind – around 15mm. You gave the sizes of the spring coils: I can't remember what size the 'new' bigger coil spring is, bit it must be in the FAQ somewhere. If you have the big coil, you don't need to do any work, supposedly. It's still worth checking the operation and tailoring your set-up as needs be.

 

I'll see how it operates in place.  The coil fits very loosely over the boss with no load applied.  Is that typical?  When you say you don't have to do any work using the larger "new" spring, does that mean filing the boss down is not necessary?

 

But what do you mean by 'making the spring hole bigger'?

If you mean the area where the spring-end hook sits. I made an indentation for it to sit in primarily to compensate for the shorter spring length, as I was using my broken spring that I had 'repaired'. Or do you mean something else?

61506[/snapback]

 

I was referring to the diameter inside the coil of the spring. On face value just enlarging the diameter of the coil seemed likea pretty clever way to solve the problem. I'm guessing that's probably not the case though.

 

Thanks for your replies on this. I hope I can get the problem resolved on this initial go at it.

 

Jim

[belfastguzzi]

I was referring to the diameter inside the coil of the spring.  On face value just enlarging the diameter of the coil seemed likea pretty clever way to solve the problem.  I'm guessing that's probably not the case though.

61523[/snapback]

 

oh... Don't think this is the cleverest way to approach the job.

Not so easy to do and it would shorten the overall length of the spring too. If anything has to be altered, best to work on that boss.

[Jim Malm]

oh... Don't think this is the cleverest way to approach the job.

Not so easy to do and it would shorten the overall length of the spring too. If anything has to be altered, best to work on that boss.

61543[/snapback]

 

 

I just delivered the shifter arm to a friend with a nearby machine shop and a nice Bridgeport mill. He will be milling the spring boss down to 15mm today. His machining skills are much quicker and more accurate than my filing skills. Hopefully, that mod along with polishing the contact point, and the new spring will allow me to do some riding soon without worry of future spring failures.

 

I did not initially realize how extensive the information on the spring in FAQ was - what a great resource it is!

 

Thanks again for the help on this.

 

Jim