Problem with loose cam chain.

Hi guys

So this is relating to my lovely breakdown thread yesterday. I finally got the bike home last night (5 hours for recovery, 3.5 of them spent waiting was a **** take) and have started to investigate the problem, which was a very loud slapping noise coming from the front cyl.

I have taken the cam cover off the front and rear cylinders and found the cam chain incredibly loose on the front, but well tensioned at the rear. I will upload some pics below so you can see the damage and exactly what i mean...

My question is what the hell has gone wrong? Presumably the tensioner? But then wouldnt the tension have gone on the rear cylinder as well? Also, is this damage irrepairable?



Front cam chain loose on sprocket



And again...



Damage on the inside of the rocker cover

Thanks

Matt

P.S. - Before anyone asks why my hands are so clean - I had just eaten some lunch before I took the rocker covers off :P

[NedSVS]

The SV has seperate cam chains for front and rear cylinders and therefore has to have a tensioner for each. If I remember correctly, the front tensioner is much easier to access and work on.

theres a guide at the front which is more than likely broken. I believe that the cam chains are indipendant of each other. you will need to remove the head to get a clearer picture of the problem. atb paul

[TSM]

rear cam chain tentioner is easier to get to than the front but sounds like the front one has broken
were there any bits in the oil?
to see the lleft chain fully you unfortunatly will have to pull the flywheel out, more than likley you have mashed up the valves of the related piston, you may get away with a new head only if the piston itself has not sustained any damage.
Pull the flywheel and you will get a better look at what happned, then you need to take the exhaust system off and start pulling the front head off to change it

[maviczap]

Originally Posted by TSM

more than likley you have mashed up the valves of the related piston, you may get away with a new head only if the piston itself has not sustained any damage.

The valves will only have mashed up, if the chain has jumped on the sprockets and altered the valve timing. By checking the timing marks by rotating the crank and lining up the marks you'll know if the timing is out.

Plus if you turn the engine over by hand you might feel if the valves are touching the piston.

Having owned Honda's will camchain problems, its not always fatal, if you catch it early. Trouble is with the SV's front cyclinder angle, if the chain is slack, then its going to rub on the chain tunnel & cyclder head, making one almighty racket

Hi guys thanks for the response. TSM - am I going to need to drop the engine in order to try what you are suggesting?? Im not bad with a set of spanners, but this is way further than ive ever gone with anything before.

Thanks

[TSM]

Originally Posted by maviczap

The valves will only have mashed up, if the chain has jumped on the sprockets and altered the valve timing. By checking the timing marks by rotating the crank and lining up the marks you'll know if the timing is out.

Plus if you turn the engine over by hand you might feel if the valves are touching the piston.

Having owned Honda's will camchain problems, its not always fatal, if you catch it early. Trouble is with the SV's front cyclinder angle, if the chain is slack, then its going to rub on the chain tunnel & cyclder head, making one almighty racket

with a cam chain that loose its near certanty that its slipped, there realy is no "catch it early" with an interfearance engine, the second its even 1 tooth out then on one engine cycle it will hit the valves in most circumstances, iknow as i was 1 tooth out on my TT engine

[TSM]

Originally Posted by ShadFX

Hi guys thanks for the response. TSM - am I going to need to drop the engine in order to try what you are suggesting?? Im not bad with a set of spanners, but this is way further than ive ever gone with anything before.

Thanks

dont think so but im not sure, you will need rad out the way, take carbs off etc at least,

[maviczap]

Originally Posted by TSM

with a cam chain that loose its near certanty that its slipped, there realy is no "catch it early" with an interfearance engine, the second its even 1 tooth out then on one engine cycle it will hit the valves in most circumstances, iknow as i was 1 tooth out on my TT engine

Lets see what ShadFX finds out when he strips it down. Pointless taking the head off, if the timing is still correct. It'll save him time & hassle, if he just turns the engine over by hand whilst its in the frame.

[TSM]

Originally Posted by maviczap

Lets see what ShadFX finds out when he strips it down. Pointless taking the head off, if the timing is still correct. It'll save him time & hassle, if he just turns the engine over by hand whilst its in the frame.

the valves could be bent and you wont know by turning it by hand, thats what i did, engine would have worked with problems, this can be tested but needs head out of frame to do a leak test on each valve
if its just the tentioner then it can be replaced, if it the camchain strip then im not sure if that can be changed in the frame, some bikes can