I got the K75 Running and the eng runs great but I have a rather loud knock coming from the trans area,I pulled the alt first and the monkey nuts look fine, I can pull in the clutch and the noise goes away(trans stops spinning), I can also put it into gear and slightly load the rear brake and the noise goes away. Splines?? U-joint?? I guess there is no avoiding pulling the back half off and seeing what is going on. Any suggestions??

Up date you can hear the same noise with the eng off trans in 1st and moving the rear wheel back and forth, seems to be coming from the front u-joint area. U=joint??

Sounds about right either way you will have to take it apart back to the swingarm to find out.
If it is just the joint don't go and buy a complete shaft new as the joint is available by itself but can be hard to find. It would pay to investigate that to start.

If time is important then a new shaft would be the way to go as getting the old one repaired could take a few days at a minimium.

Thanks,I plan on pulling it down tomorrow and I'll take pic's and let you guys know whats going on.

Well boys the bad news is in, NO lube on trans input shaft,rear splines and driveshaft and u-joint ok. Needs trans input shaft and new clutch.Looks like prior owner just ran the crap out of it and negelected to do what was needed.

Trans also has about 40 dgrees of play between output and input shafts. So the trans itself has some bad internal wear.

Pulled the from cover on the trans and do not see anything to be concerned about,no metal in trans,fluid clear,all gears look good with no abnormal wear showing especially on the bevel gears of the input shaft.
Do you guys think i'm being too paranoid about the trans play??

chris i did a little survey a while back .....and with bike in gear , and moving the back tyre between stops and taking a measurement on the outer part, we found 50- 60 mm or there abouts was a pretty common finding ...i dont know how that transfers to your angle measurement

this movement takes into account the bevel box and gearbox movements.....i thought it might give a clue to what is normal with out dissasembly .

sad to hear about the input shaft and clutch

chrish8846 wrote:
Do you guys think i'm being too paranoid about the trans play??

Chris i have to agree with Charlie,that's normal. How many miles on the bike ??
i sure hope it's not them 1985 6 rivets loosening up !!!! But.... you said the noise was gone with the clutch lever pulled in.

looking at the pic chris ....there seems to be more wear towards the transmission end of the splines ....can you confirm that the wear is even all the way around ...?

if it isnt ..i think you may have found your problem ....my guess is that there is a bearing issue on the input shaft ...

Wear is even all the way around, I think the noise was the excessive clutch spline wear,sadly I also have a lot of wear on the input shaft splines, almost down to a knife edge closest to the trans housing. I'm thinking it's too bad to reinstall and feel safe.

i agree ....while you have it apart ...best to make it all good .....good luck mate

seems to be a lot of trans on e-bay lately between $150 to $300. if you can find one local you won't have to pay the big $$ for shipping.

The play you quote is quite normal and would be of no concern to me but the shaft needs to be replaced.
I would use it at a pinch but only till I could replace it without delay as it would wear the clutch spline.
With the cost of a new shaft you would be heaps better off getting a good second hand box with low miles.

I bought 2nd hand box off ebay for 125.00 plus shipping, much cheaper than trying to source new parts.Dealer says splines are good, they look good in pic's and I can return if not happy. Now I just have to tell my wife it will be another week of walking around the bike in the garage.
She will love that as it blocks her kiln and pottery stuff.

oh ?!! good work chris ...

I'm doing some prep work on the fairings and side panels and chin spoiler, they will be ready to paint today so they will all be ready when I get the trans delivered. I'll post pic's when it's done.