k75 skipping out of gear

[bavareze]

Hi guys.  Had this great k75 for over 5 years now.  purchased with 55k miles, now at 65k miles with no issues.  Until last week.

In second gear sometimes it feels like the bike is momentarily (for 1/2 seconds) losing traction.  As if the bike would jump from the 2nd in N and then back to 2nd, after fraction of a second.

I had similar issue 6 years ago with a Honda VTR and it turned out to be the drum and one sprocket in the transmission. 

What do you think?  Is this kind of problem common? 

Just in case I need to replace the trans, is there a DIY for it?

Thanks!

[roninvt]

Hi bavareze,  under what conditions does this occur....and does it happen with any other gear?  Could be ur clutch is slipping.  My bike has come out of gear with a woosy shift, but has never re-engaged itself.

[Chaos]

very early K75's  (86, 87) had shift drums with bad metallurgy, which could cause bent shift forks and jumping out of gear.  I have not heard of one jumping back into gear though. That does sound like a clutch issue.  Drive shaft splines could give up, but I don't think they could start engaging again.  Transmission removal isn't too hard, if it is the gearbox your best best is to find a good used one, usually under $300, cheaper than the parts to repair yours. 

[bavareze]

mine is 1991. 

maybe it is not jumping out of gear then.  the overall feeling is that the bike loses traction suddenly for a fraction of second and then resumes to normal.

splines looked good a few months ago when I lubricated them.

so I will look on ebay for a gearbox

[Scott_]

When you lubed your splines, by chance did you check the thickness of the clutch friction disk?
It's possible that it's just the disk getting too thin, and your transmission could be just fine.

[johnny]

if this were my deal i would make sure my aaa is paid and then i would just keep on gassing it and stop freaking...

j o

[Mongrel]

I've had this happen to be very rarely. Much more common is what Chaos described, shifting to 2nd and then dropping to neutral. Though even that stopped happening much, after I got in the habit of shifting more firmly (aggressively) and being sure you feel the lever click twice on the way to 2nd.

These beasts have notoriously "funny" shifting, so it's certainly something to be aware of.

[Scott_]

Much more common is what Chaos described, shifting to 2nd and then dropping to neutral.

+1 BTDT, It happened to me when I started riding with a new pair if different boots. Lazy shifts. Didn't matter what gear it was.
I basically had to remember to be strong with my shifts. As long as it wasn't a lazy shift it didn't drop out of gear.

[75rtpaula]

i had this same problem that i just fixed on my 95, it turned out to be the 1-2 shift fork was worn down a whole bunch on the 2nd gear side of the shift fork, replaced the shift fork and all is perfect now

before i fixed it mine was having a problem that sounded exactly like the one you are having

[bavareze]

finally got it removed.

found a few on ebay 87-88.  mine is 91.  would those fit?  is there something in particular I need to check?  thanks!

[K75RT Keith]

All the K 4 valve monolever transmissions are the same.  Case color might be different but that's it.  What should you look for?  Besides the obvious, worn splines, worn or chipped gears, bent forks, worn bushings, wasted bearings or a damaged/cracked case.  Nothing.   

Might be just as far ahead to hunt down Bruno's and have your old one custom built.

[nortonbrian]

Usually the dogs get rounded off on the second gear. The gears then are trying to force themselves apart, that puts pressure on the shift fork and the shift drum resulting on more wear.   When this "slipping" occurs, try backing off the gas and the dogs may get better engagement.
A typical repair would be a pair of gears, shift fork and drum, minimum. I agree, best repair is a used tranny, keep the old one, tear it apart and see how it all works.

[johnny]

shifting at the redline works for me...

it takes a while to get used to the hi-rev screaming when tached at the redline... butts i tells her to shut up or walk...

j o

[bavareze]

I agree, best repair is a used tranny, keep the old one, tear it apart and see how it all works.

got used low mile trans from ebay for under $200 shipped.  works like new.  I'm eager to take old one apart too !

thanks for the help!