chain derail

F

fenshui2002

New member
Hi all,
this is my first post so i shall introduce myself. My name is Alan from the uk. I Bought a 2006 ec250 About 6 months ago and i have a problem!
I changed the chain and sprockets on the bike about 4 months ago. Since i have changed them i have noticed the chain keeps going slack which has become a pain in the ass because i have failed to finish my last 2 H&H events. Despite tightening the chain before everytime i use the bike it derails. Its almost as if the chain as stretching.
The front sprocket is a Renthal, rear RFX and the chain was a DID. The chain is now a write-off as it was caught between the frame and swingarm in my last event and now twisted.
I have changed many a chain on my road bikes, and chains on my last 3 off-road bikes and never had a problem with this in the past. So therefore im a little stumped to why the chain keeps coming off??
I have thought of a few things it could be- maybe the DID chain is faulty. I doubt it, but im gonna change it so i will find out soon enough. The other was my front sprocket out of line. Maybe i have fitted it the wrong way around. I have fitted mine with the groove side out (smooth to the engine), is this the way others have fitted theres?
Finally does anyone have chain rollers on their '06 bike near the front sprocket on the lower run of the chain?
Sorry for the long message but if anyone has any suggestions or advice it would be great.Thanks
 
Not sure if the 06 frame was similar to the 2010/2011 in regards to how the side stand and lower chain roller is attached, but if it is its very possible its snapped off at some point and never been fixed. See this thread - http://www.gasgasrider.org/forum/showthread.php?t=14099 - some pics on the second page.

Also are sure the chain is tensioned correctly? If it is over tightened it can cause damage and stretching to the chain at best. It can also results in the front sprocket shaft bending. The chain needs some slack at the tightest point (swingarm half way through stroke), which means you'll expect even more when resting normally. For me this is about 2-3 fingers between the rear of the swingarm chain guide and the top chain.
 
You didn't say if the new chain was an 'o'or 'x'ring or neither.A non o ring chain will stretch and stretch from the word go.I fitted a regina non o ring once.It bearly lasted 20hrs.Never again.
 
gasmonkey said:
You didn't say if the new chain was an 'o'or 'x'ring or neither.A non o ring chain will stretch and stretch from the word go.I fitted a regina non o ring once.It bearly lasted 20hrs.Never again.
Click to expand...

It was a non o-ring. I knew they didnt last as long as an o-ring but i didnt think it would last as short a distance! I mean... why make a chain that only last 5 mins, lol. I thought with DID being a decent brand it would be ok. Anyways, i have order an o-ring chain this time around to eliminate a possible cause.
Thanks
 
Jakobi said:
Not sure if the 06 frame was similar to the 2010/2011 in regards to how the side stand and lower chain roller is attached, but if it is its very possible its snapped off at some point and never been fixed. See this thread - http://www.gasgasrider.org/forum/showthread.php?t=14099 - some pics on the second page.

Also are sure the chain is tensioned correctly? If it is over tightened it can cause damage and stretching to the chain at best. It can also results in the front sprocket shaft bending. The chain needs some slack at the tightest point (swingarm half way through stroke), which means you'll expect even more when resting normally. For me this is about 2-3 fingers between the rear of the swingarm chain guide and the top chain.
Click to expand...

Ah, thanks for the thread. Thats interestng, i shall have a good look on the weekend. As for the tension i use the 3 finger rule and checked the swingarm through the stroke. Double checked infact, so im sure it isnt that. It's fine until i set off. After reading the thread though i have a feeling that i am minus a roller and that there is ment to be one there, i have seen lower bearings for sale for my model but couldnt see where it was ment to be mounted.
Thanks
 
Rick said:
Is the wheel correctly spaced? Correct spacers on the sprocket side?

Is the counter shaft sprocket on the correct way? Meaning is the offset, center line of the sprocket in line with the rear sprocket?

If you have a laser, small house hold one, you could check aligment that way or use a http://www.motionpro.com/motorcycle/partno/08-0048 or
http://www.bikebandit.com/profi-laser-chain-belt-alignment-tool
Click to expand...

Yeah, the wheel is correctly spaced as they have different spacers to suit the extra bearing on the one side of the wheel. Im not sure about the front sprocket (i copied the one that came off the bike- nothing to say the previous owner put it on the right though). This is one of my doubts, i was hoping someone could tell me how theirs is mounted to the bike (smooth side inside or outside to engine). I dont have a laser but maybe a bit of string will do the job? Thanks
 
You must log in or register to reply here.

Similar threads

Wbdisco
Case saver??
Replies
13
Views
3K
Wbdisco
Wbdisco
M
Engine surge/runaway?
Replies
4
Views
162
Mustyeddie
M
S
2021 EC250 for sale
Replies
0
Views
1K
sfiegen
S
N
Front sprocket thing and random leakage
Replies
12
Views
3K
Zman
Zman
H
Almost new 2002 or 2003 400 FSE
Replies
6
Views
2K
husaberg
H
Back
Top