A few concerns...

[Freza]

Hello,


I was wondering if you're familiar with these symptoms that I recently started having:


1. Clutch doesn't release smoothly. It comes to ~90% of being released, then suddenly releases completely. It creates "kick" when starting on green light, and it is probably not good for whole transmission / chain.
I changed clutch plates a year ago, they're not worn. What could cause this ?


2. Something develops noise on exactly 6000rpm. It sounds like school ring, only less loud. It's fast paced metal noise, as if you take two metals and hit them gently one to each other very fast (maybe 10-20 times / second).


3. Last year my front left fork leg blew its oil seal. I had replaced seals and oil in local bike repair shop. Ever since, I don't feel confident in front end, although everything works as it should. Forks squeak when they run over dents (deeper dents, when they need to travel a lot) and something knocks somewhere in the front end (doesn't matter if brakes are applied or not).


4. I think that engine creates more vibrations in higher RPMs. I'm no mechanic, so pardon my ignorance, but does this engine sit on some kind of bushings? Maybe they need change? After all, it has ~35.000 miles.


5. The engine starts difficultly when it's hot. When it's cold, it's OK although not perfect, but when it's hot sometimes I have to start it several times for it to actually start, and when it does, it starts barely. You can almost hear cylinders firing up one by one until it stabilizes after 1-2 sec, then it's ok.
After that it works fine, it has power and doesn't exhaust strange smoke, although you can smell gasoline strongly until it stabilizes.
A friend says it's the problem with carburetor, it doesn't mix well or is in need of changing some rubbers inside (don't know exactly). What do you think?

6. My front brake lever feels "sticky" and bumpy on the start of the travel. It didn't do that until recently. Is there an easy way to fix this, maybe to lube something? Or do I need to take it to mechanic to bleed possible air ?




Thanks

[andybesy]

Hello Freza,

There's a lot there, and I'll leave some of the more technical queries to more experienced people.

1) I'll have to leave this to others.

2) But on point two, I'd start by just checking for things rattling. The fact that it's at a particular RPM, and near the resonant frequency of the bike, suggest it may be this simple. For example I had a similar sound at one stage and tracked it down to on of the chain tensioner things not being, err, tensioned. I.E. it had a little play and would give a metallic rattle at times. Tightened that up and simply fixed. Once you've checked for simple things like this you can then move on to looking at more complex causes if need be.

3) When my front wheel bearings went I had a similar loss of confidence in the front-end, long before I realised they were the problem. It just shows how sensitive we are to the handling that a loss of confidence which you can't quite put your finger on is the first recognised symptom. I'm sure steering head bearings would be the same. I would start investigating this point by checking front wheel and steering head bearings. Put the bike up on it's centre stand and check for play both forward/back and left/right. Ask a friend to put the weight on the rear raising the front wheel, and using just a single finger on the handlebars check fro free movement, and feel for any notchyness. Place the bars centrally and let them fall, doesn't matter if they fall left or right but they should fall all the way by themselves.

4 and 5) When was the last time you had the carbs balanced? Is there any lumpiness at idle? Are the carb rubbers in good order (no cracks etc)? Is the chain and sprocket set in good order? I.E. no tight spots, sticking links, excessive wear?

6) Begin by ensuring lever mechanism is clean and greased. Maybe as simple as some grit in there. Air or water in the fluid would feel spongy.

Hopefully I ask some useful questions to get things started.

Andy

[Freza]

Thanks Andy.

4 and 5) I really don't know. It may have passed a few years. I also don't know in what condition carbs are. I should probably have it investigated once the summer is over.

6) yes, it's probably this. I'll have it greased and report back.

[darrsi]

Try and adjust the clutch properly at the bottom end first, then the top end, it may just need a tweak.

I'd be more inclined to get things sorted before the summer is over, may as well make the most of any decent weather we might get.  8)