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bikr003
22nd August 2008, 12:49
Was riding in this morning when i noticed my engine was making a funny sound when down shifting. Kyle took me to this biker shop and the guy said its my cam chain. I would rather do it myself and get some experience. Has anyone done it before who can help me out? give me a few pointers! hopefully i just have to tighten it rather than replace it!!!

FJRider
22nd August 2008, 13:22
Just let the bike shop do it, otherwise the experience will be BAD. With the aid of a workshop manual, you could do it, but to explain clearly on this forum.... It is NOT just "tightening" something. It DOES cost, but there may be more wrong than "loose" issues... :calm:

R1madness
22nd August 2008, 15:51
GPX250s have an automatic cam chain tensioner (It hides on the right hand side of the crankcase behind the barrels and below the carbs) so you cant just tighten it. Howerer the tensioners on this model are prone to failure not so much the chain. Get it done by a shop. but get them to inspect the tensioner first. Its a easy check and should only take about 30 mins.

motorbyclist
22nd August 2008, 22:53
hi, after talking to you today i reckon we check the tensioner, and if the chain is infact going give it to a mechanic - way too much effort for a reasonably cheap job

Patar
22nd August 2008, 23:09
my friend recently bought a gpx250 and his cam chain skipped a couple teeth and messed his engine up something fierce. It was most likely due to a worn tensioner and as a result the cam chain was vibrating too much. It ended up with him getting a whole new engine.

I'm not sure what the exact layout is on the gpx's but replacing the tensioner is very easy and cheap, but I don't know if you can check the chain condition when replacing the tensioner.
If your chain is getting worn it would be a good idea to replace chain and tensioner, otherwise it should be fine just replacing the tensioner.

2wheeljunkie
23rd August 2008, 14:46
what have u decided to do ben?? u work on it today?

Squiggles
23rd August 2008, 16:33
Question, does it make the noise only when in gear and with the wheel rolling, or does it only do it in neutral?

2wheeljunkie
23rd August 2008, 16:52
it does it in neutral but when you rev it, it gets worse..

FJRider
23rd August 2008, 20:59
Get it seen to. The longer you leave it, the more chance it will (may) jump off the sprocket ...and then the REALLY expensive stuff "happens"...really fast.
But the good news is... when that happens, the "rattle" will STOP...:calm:

PirateJafa
23rd August 2008, 21:17
Get it seen to. The longer you leave it, the more chance it will (may) jump off the sprocket ...and then the REALLY expensive stuff "happens"...really fast.

Ha!

10char.

bikr003
25th August 2008, 09:06
well i took off the tensioner and put it back as per the manusl and it still noisy so it prob is the chain any recomendations on where to get it done. another slight problem is i booked my restricted 4 next tues. !!!! this is fun ha ha.

R1madness
25th August 2008, 09:38
simply pulling the tensioner off and putting the same one back on is not really going to do anything. What did you find when you took it off? Was the plunger worn? Did it slip on the tensioning blade? Most shops will be able to do the chain with no problems. Just ring around and see who can do it in time for ya.

Patar
25th August 2008, 10:02
taking off and putting back on a worn tensioner won't do jack all.
You have to replace the tensioner, go to mt. eden motorcycles they can order you one in (only takes a day or two).
If that doesn't fix it, then the chain will have to be replaced aswell.

If you're going to get a shop to do the cam chain for you, you might aswell get it a full service while it's there (valves etc.)

2wheeljunkie
26th August 2008, 16:20
taking off and putting back on a worn tensioner won't do jack all.
You have to replace the tensioner, go to mt. eden motorcycles they can order you one in (only takes a day or two).
If that doesn't fix it, then the chain will have to be replaced aswell.

If you're going to get a shop to do the cam chain for you, you might aswell get it a full service while it's there (valves etc.)

he took it to a guy out in tamaki..nice guy..then he was my pillion bitch..bahahahaha

Patar
26th August 2008, 18:49
I'm slightly annoyed with honda atm.
My bike has recently clicked 50k so i'm taking it in for a service, but of course to get the cam chain/tensioner checked can't be easy on a vtr. ARGH.

shingo
26th August 2008, 18:51
I'm slightly annoyed with honda atm.
My bike has recently clicked 50k so i'm taking it in for a service, but of course to get the cam chain/tensioner checked can't be easy on a vtr. ARGH.

Have heard they're a real bitch to change and cost a pretty penny as well.

Tho i know of a one with 78000+k's on it yet to need the cam chain changed, so hopefully yours will be the same.

motorbyclist
26th August 2008, 23:42
50k with no known problems and you're annoyed?

guess there's just no pleasing some people;)

Zealot
27th August 2008, 00:48
Yea, that was really gay. A $30 part costing me $700 for a new engine. It's quite crap. Oh well. C'est la vie. If anyone wants a tensioner for a GPX250 cam chain let me know, I've got an unused one (no point putting it in the new engine, it's from an '07 bike). Also bought a chain breaker and chain to swap cam chains, then realised that the head was screwed, rather than the timing just being out. Sigh. Cost me probably $1k all up.

motorbyclist
27th August 2008, 01:10
ouch - it's stories like that really make me wish people were more mechanically inclined (or at the very least paranoid)

Patar
27th August 2008, 16:50
Have heard they're a real bitch to change and cost a pretty penny as well.

Tho i know of a one with 78000+k's on it yet to need the cam chain changed, so hopefully yours will be the same.

Yeah it's not the chain I'm worried about, it's more the tensioner. And sadly I have neither a garage nor proper tools to do it =/

FROSTY
27th August 2008, 17:03
Dude yes the tensioners arent the very best in the GPX's
but Ive had some luck with giving the tensioner a little nudge so it clicks over to the next "groove"

Zealot
28th August 2008, 00:20
Yep, turns out that a cam chain failing due to the tensioner being loose sounds exactly like valve clearances being a bit bad (ie tappets). I went meh... didn't do anything much, and it went boom. :(