CT110 guru advice sought

[DR]

I find it hard to imagine I'm posting a question pertaining to a mighty posty bike but alas a friend with one has issues.... (obviously )

I'll probably be the poor sucker who gets the job of repairs but before I even contemplate the job is there a common issue that causes a very audible knock in the transmission upon clutch take-up or any given load?

Lets' play charades for a bit sounds like a gear with chipped tooth or worn dogs but there is no jerk as such when it clunks. It seems to rise with engine/clutch speed but only when in gear with brake dragging or when actually riding. Gearbox oil doesn't seem contaminated with iron fillings but this may have been changed recently as it seems too clean to be true Bike has been sitting for well over 12 months but under cover which really shouldn't be a problem...would it? Clutch plates sticking or something stupid mayhaps?  The clutch seems to take up okay upon riding and the gearbox feels nice otherwise. The wheel and tranny turn over smoothly with no roughness or noise when the bike's on the centre stand so WTF gives! Another good description is it feels like a front sprocket bolt is hitting something in the case but this isn't happening as it rises with engine speed but it just sort of sounds like it. Any ideas anyone

[monaro308]

I dont know if this helps Doc
http://ct90-ct110.com/
There are PDF manual files in there.

My CT90 has a bolt on the bottom of the left side case with a spring loaded plunger for the cam chain tensioner,whether you have a sloppy cam chain i'm not sure.
I think Leith said that he works/worked on postie bikes.
Sorry i couldn't help.
I suppose my CT90 Trail counts as a dirtbike?

[TT]

I've got a couple fo these Doc, but never heard a noise like that.
It does sound like a chipped tooth though. Maybe on the clutch basket?
I've got one apart on the bench at the moment because it's crapped 1st gear (common for an ex-postie bike)
Maybe it has other gearbox damage that caused this?
I've got manuals and maybe even the bits you need too. 
I've probably got gaskets too.
You're welcome.......... 

P.S. I'll post this on ADV Rider. Lot's of guys with postie knowledge on there.

[Tim754]

Have met with your precise problem before Doc ,on both machines a gearbox strip and rebuild was required to replace the components. One machine had a very sad 1st gear set, the other had lost a tooth off 3rd gear that had moved around in the box!.   BUT if possible (a spare engine for parts thing) try replacing the auto clutch unit first then try Tim754

[DR]

Bugger! sounds like I'm going to have to clean my bench and prepare for surgery thanks for the leads people Am I to imagine the 78-82 pdf manual I pilfered from Mario's link will be basically the same for all models 600BC to current? Not sure what year I'm looking at yet but it'd be early 90's I'd say from the condition of things. Tony I maybe in touch depending what I find but I'm not looking forward to this at all. Are you coming to CD7! Maybe I could bring it with me and you could spend the whole 4 days fixing it. I'll even give you a 6 pack for your troubles!! Me simply learning to say no in the first place would go a long way to fixing problems like these

[LWC82PE]

I service these for Aus post so i know that you gotta watch the chain tension and get it right. If its just a bit too tight the chain pulls on the counter shaft and creates a horrible clicking noise.

[Noel]

does it happen in all gears
Noel

[DR]

Leith, I'll have a look at that but the engine sounds sweet and the whole bike in general doesn't seem to have had a spanner put near it in recent times. Noel, something I didn't check was if it happened in all gears Will report back on that tomorrow

[crs-and-rms]

hey doc i have a manual i can down load  if you need a copy i to work on these ct110 we have the aust post contract where i work

[holeshot buddy]

come on doc admit it its really yours

sounds like a weak big end

[TT]

Hey Doc:
Here's the replies on ADV rider.
http://www.advrider.com/forums/showthread.php?t=571316
I tend to think it's a tooth missing somewhere.
Yep, I'm coming up to CD7 and more than happy to swing by and help out on the way there or back. You just have to supply some floor space for me to sleep between shifts, eh??
I've got spare parts, so if you get it apart I can either send up what you need or bring it in June.

[DR]

tanks again blokes CRS and RMS, I'll see how I go in regards to the manual as it's probably similar to the 1 I've pinched online

Russ I once entertained the notion ...but seriously ... NO!..2 Honda's already is 2 too many

[TT]

Someone just mentioned checking the clutch and primary drive nuts too. They're quite often not done up tight because it needs a special tool.
I've got one so let me know if you need it and I'll post it up.

[DR]

thanks Tony, I'd really like love it to be something simple under the clutch cover as I really don't want the job of pulling the motor out and splitting it I haven't been back to try the other gears which will tell me a lot more..can't rush these things

[TT]

They're really easy to work on, Doc. You'd have it out and split in half an hour if need be.
Whatever you need, let me know.