Needle bearing in clutch basket

[dirtbike]

Has anyone replaced that bronze bushing in the clutch basket with a real needle bearing. I think I will. That 22mm outer diam and 16mm shaft diam seems like a real standard size to mee. Perhaps the same approach can be valid for the piston pin bushing.

anybody ??
//B Hahn

 

[Doug Wilford]

bengt   The aluminum rod was the only one to use the bushing for the wrist pin, if you want a bearing use the steel rod.   In both cases there were no problems with either bushing, save your money.

 

[john durrill]

bengt,
 the bronze or steel bushing has a lot more bearing contact than a needle bearing does.
 the Plain bearing ( bronze or steel) was used in Sachs 175/6 GS engine. It uses a lot of the same parts as the one you have. It held up well in it. I never had one fail and rode one 72 in enduros for 3 years with out a problem
 John

 

[dirtbike]

Well I have a steel rod but still a bronze bushing. I don't know if I will do anything about that but the center bushing in the clutch basket is too worn for my taste. There is a significant gap and I wanted to replace that one with a needle bearing.

Is there a good reason why I shouldn't ?
//B Hahn

 

[paavojaelvis]

Bengt,
the clutch basket may not be enough hard to cope with the stress from needle rollers, so at least you should use a bearing with an outer race. An INA HK type could be fine. For 16mm shaft there are three std sizes: HK1612, HK1616 and HK1622. The two last digits indicate width, all with 22mm o/d.
Make sure, that the shaft itself is not worn out and has no pitting. I would leave the con rod as it is, supposing you're not going to take out the very last HP:s from your engine...  

I hope this helps a bit.



w/rgds:
Paavo Pernu
Technician,Age 39
KTM 125 GS  -77
KTM 125 GS6 -78

[john durrill]

Might be an idea to make up a slightly undersized bushing from bronze bush material.
 make sure and shim up the end play or clearance between the cluch hub and the snap ring so you have .002 to .004 of an inch end play.
Per the sachs repair manual.


 

[dirtbike]

Terve Paavo!
Pratar du svenska ?
Anyway your idea is exactly what I had in mind. HK1622 is what I had figured. The shaft is fine, not worn and there is a small lubrication hole there that I figured would be ideal. I'm not into the idea to make a new bushing with the precision that the application demands yet not as good as a needle bearing, from my point of view.

 

[paavojaelvis]

Kära Bengt,
det syns, att vi måste tala (skriva) bara på engelska, jag är ganska tråkig med svenska, tyvärr. OK, if the shaft is in pristine condition, as you said, go ahead. But be careful with shimming to get the right amount of end play, as John highlighted above.

rgds
Paavo