Clutch Problem

[rippedfromhell]

Hello,

I was hoping someone could give me advice on a problem which I cant quite pinpoint but I believe my be related to the clutch in some way.

Before I explain I would just like to note that this only ever seems to be a occur when the bike is cold and in first gear but I can change gears no problem

I have noticed when I let the clutch lever out in first gear the bike starts to move forward as usual then there is a loud thudd and the bike shoots forward like I have just dropped the clutch to fully open and the bike shoots forward. I can pull the clutch lever and momentum stops but then as soon as I let the clutch out again it happens again. 90% of the time this never happens on a cold day but when it does its a scary experience to say the least.

There is one other thing that may or may not be related to this problem (in any gear). After starting the bike from cold and it begins to idle, there is a deep thudding sound (different, less violent thudd from the other issue) that repeats every few seconds that seems to be coming from below the tank. Again this stops after about 30-60 seconds of idling but I must mention this is the same sound I got just before my starter motor blew a few months back (replaced it with a new one from Honda).

Initially I thought it was the chain slipping so I replaced it with a new DID chain + new sprockets, oiled change, air filer changed and cables oiled but no luck.

Any Ideas/ advice would be much appreciated.

Cheers.

[Wicky]

Have you bled the clutch, and that the level in the reservoir is okay?

Also what's the condition of your cush drive rubbers like?

There is one other thing that may or may not be related to this problem (in any gear). After starting the bike from cold and it begins to idle, there is a deep thudding sound (different, less violent thudd from the other issue) that repeats every few seconds that seems to be coming from below the tank. Again this stops after about 30-60 seconds of idling but I must mention this is the same sound I got just before my starter motor blew a few months back (replaced it with a new one from Honda).

Can you video this peculiar phenomenon with sound, and post it.

[rippedfromhell]

I will certainly try but the sound quality on my phone camera is dire, so not sure it will pick it up over the exhausts but ill give it a shot tomorrow.

[benny hedges]

you need to strip the clutch and check for warped / blued metal plates.
and broken / cracked friction plates.

also check the pushrod behind the gearbox sprocket cover is clean and as wicky said, be sure there is no air in the hydraulic system.

when did you last change the oil??? and is the oil level ok>?

the thud under the tank is carb fart. fit a new set of plugs, check the condition of the airfilter and balance the carbs.
also up the idle speed a bit - 1200 - 1500. i run mine at 1500, also helps reduce engine braking a bit.

[tony.mon]

Agree with Benny.
The carb cough is not connected.

Clutch-wise, you may have a leaking slave seal, master cylinder seal, dirty pushrod, ir a few other things.
First clean, bleed and check the master cyl (handlebar end of things) and the slave cylinder and pushrod (near your left foot).
If not, you'll have to empty the oil and coolant, take off the water pump, and remove the clutch cover and have a look.

[rippedfromhell]

Thanks chaps.

I'm going to strip it down at the weekend again but last week when I did it the plates looked in good shape and push-rod seemed clean enough. Cylinder levels are fine but Going to take your advice and drain the cylinders to see if there is some air in there that could be the cause.

Carb farts.. The oil + filter and air filter where changed 3 weeks ago and the oil level is good. iridium spark plugs fitted aprox 5/6 months ago. I have had my idle speed set at 1200 but just upped it this morning to 1500 before my ride into work.

[rippedfromhell]

Found a post here where someone else seems to be getting the same problem:

http://www.fixya.com/motorcycles/t6748756-vtr_firestorm

one of the solutions is to look at the 'clutch plate is too close for engagement.' I ill have to look into how to adjust the plates.

[benny hedges]

I ill have to look into how to adjust the plates.

you can't adjust them.
buy a barnet clutch, basket & plates. sorted.
or a sigma slipper clutch if you have a spare £600

[Wicky]

Apart from the advice to check the clutch plates, you won't get far trying to adjust the clutch cable ;-)

Found a post here where someone else seems to be getting the same problem:

http://www.fixya.com/motorcycles/t6748756-vtr_firestorm

one of the solutions is to look at the 'clutch plate is too close for engagement.' I ill have to look into how to adjust the plates.

[Chrismech]

An old thread I know but.. I have the same problem (amongst others!) with my VTR (1997 1000F) (I have noticed when I let the clutch lever out in first gear the bike starts to move forward as usual then there is a loud thudd and the bike shoots forward like I have just dropped the clutch to fully open and the bike shoots forward

) Anyone had this and solved it?

I'm guessing It's something with the clutch itself but would be useful to know if its normally a worn basket for instance

[Wicky]

Check the fluid level in the clutch resoirvoir - change the clutch fluid and bleed system. Check for leaks and condition of seal on clutch slave.

[VTRDark]

Sounds like a serious case of clutch judder and/or slip to me. Bleeding will help but wont cure the judder. Make sure the clutch pushrod is straight and the right way around too. These are not the best bikes for letting go of the clutch, slow steady clutch control is the way to go.

(:-})

[Chrismech]

Ok thanks guys I'll give the hydraulics a good bleed and look over -

Haven't done many miles on the bike yet but this fault has only happened twice - first time thought it was my lack of clutch control but happened again this morning - otherwise the clutch is smooth and light and doesn't slip - biting point is right at the end of the lever though

[tony.mon]

it will happen every time you try a drag strip style getaway, and as you raise the revs to meet the bite point and induce some slip it will bite, lock and try to throw you off the back.

They do that.