Just been reading a thread on SuperHawk forum about changing CCTs to APEs which I did 2 weeks ago. Thread mentioned a click when removing autos and this means engine was not at TDC and timing chain has clicked over. When I did my front cylinder I heard click but thought nothing of it until I tried put the manual in, as it would not seat properly, anyway took off front cam cover and timing looked all ok. Put APE in no prob then put all back together and all is fine.
What symptoms would I get if the timing had jumped slighty out?
Matt
Timing question
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benny hedges
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Re: Timing question
depends what you call slightly out................
it only has to jump 2 teeth to hit the valves against the piston
dunno what symptoms you would get - if its an inlet cam timed up wrong you might get a lot more backfiring through the carb or burnt valve seats if the valve is still slightly open when it fires, if it's an exhaust cam you might get exhaust backfiring and really flat performance, and burnt seats.
chances are if the chain has jumped the cogs then both cams will be off...
might be worth pulling the cam covers and checking the timing if you're not sure...
did you remove both cam covers when you fitted the apes??
you need to be able to see the cams are not on the lobe with valves under spring tension before you remove the cct.
i know in the guide on here it says just remove the front cam cover, but for what it's worth, it's a lot easier to get the back one off and for peace of mind it's worth removing it to check, you only have to remove the 4 bolts and the breather hose - and also it's easier to remove the camchain guide on the back pot to gauge correct tensioner tension by feeling the chain between the camshaft cogs.
just be sure to use some loctite if you take off the guide - dont ask!!! memories of cb250rs and broken brand new yoshi cam
it only has to jump 2 teeth to hit the valves against the piston
dunno what symptoms you would get - if its an inlet cam timed up wrong you might get a lot more backfiring through the carb or burnt valve seats if the valve is still slightly open when it fires, if it's an exhaust cam you might get exhaust backfiring and really flat performance, and burnt seats.
chances are if the chain has jumped the cogs then both cams will be off...
might be worth pulling the cam covers and checking the timing if you're not sure...
did you remove both cam covers when you fitted the apes??
you need to be able to see the cams are not on the lobe with valves under spring tension before you remove the cct.
i know in the guide on here it says just remove the front cam cover, but for what it's worth, it's a lot easier to get the back one off and for peace of mind it's worth removing it to check, you only have to remove the 4 bolts and the breather hose - and also it's easier to remove the camchain guide on the back pot to gauge correct tensioner tension by feeling the chain between the camshaft cogs.
just be sure to use some loctite if you take off the guide - dont ask!!! memories of cb250rs and broken brand new yoshi cam
You do not have to say anything. But it may harm your defence if you do not mention when posting something which you later rely on in quote. Anything you do say may be ripped to sh*t.
Re: Timing question
I only took off the rear cover at first then when I came to do the front APE heard the click when I took the auto CCT out, then I took the front cover off to investigate. But all looked ok. I had a thought this morning that if there was a problem wiyh the timing then the plugs would look dodgy so just had a look at them and they are fine, and I have had a few long rides since I have done them. I do get some popping on the over run but she has always done that. Just being CCT paranoid I guess. 
Re: Timing question
After you'd set the rear cylinder's cam timing, did you then rotate the engine the right number of degrees to the timing point for the front one?
If you left it where it was for the rear one then you need to check the front timing settings again, because if you have the engine at the correct point for the rear one the front cams will be pushing down on the springs and at that point are likely to turn as soon as you relieve the chain tension by removing the tensioner for the front cylinder.
If you turned the engine to the correct place for the front cylinder, following the instructions on here carefully, then you haven't got a problem, assuming you got the lines on the camshafts level with the head with the front on FT.
BTW, the front cam sprocket marks are difficult to see; it's easiest to drop the LH rad off to make the job easier.
If you left it where it was for the rear one then you need to check the front timing settings again, because if you have the engine at the correct point for the rear one the front cams will be pushing down on the springs and at that point are likely to turn as soon as you relieve the chain tension by removing the tensioner for the front cylinder.
If you turned the engine to the correct place for the front cylinder, following the instructions on here carefully, then you haven't got a problem, assuming you got the lines on the camshafts level with the head with the front on FT.
BTW, the front cam sprocket marks are difficult to see; it's easiest to drop the LH rad off to make the job easier.
Last edited by tony.mon on Mon May 10, 2010 6:49 pm, edited 1 time in total.
It's not falling off, it's an upgrade opportunity.
Re: Timing question
Hi Tony yea defo followed instructions to the word even printed it off and took to garden. I think its all ok as bike is running sweet.I think if anything was wrong it would have shown on the plugs I have done about 400 miles since I done em including 200 mile round trip to Hastings on BH Mon and plugs look fine.
Matt.
Matt.