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2 questions...this is for clarification only
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  (#1)
TPG - screw face
 
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2 questions...this is for clarification only - March 3, 2009, 07:31 PM

questions #1.

info: the 1999 GSXR 750 had a recall on the OEM spring loaded CCT when Suzuki finally owned up to their mistake. In many manuals, you will see a locking mechanism, but in the CCT's they manufactured, there are none.

question: Should you be able to hold the CCT in your hand and push the tensioner back and forth with your hand? From my understanding, there should be a locking mechanism that prevents this as the spring is supposed to go in one direction, out...thus tightening the cam chain over time due to wear and tear....confirm? thoughts?

question #2.

info: a leak down test is done yielding an extremely high percentage of leak down

question: can a leak down test yield fabricated results if the cam chain is off by 2,3,4 teeth? Assuming TDC must be achieved prior to performing the test...if TDC is set, but with incorrect timing, what kind of results can one expect?

thanks for any replies
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March 3, 2009, 09:15 PM

1) No.

2) Yes. If the timing is off far enough to have a valve not fully seated leakdown results wouldn't mean squat.
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GP Champ
 
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March 3, 2009, 09:31 PM

The cams or cam would have to be off so much that piston to valve contact would have already done the engine in.
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March 4, 2009, 08:52 AM

The cam chain tensioner could cause the valves to slightly contact the pistons, bending them slightly and causing leak down. it would not give faulty readings on leakdown. It would give bad compression readings if it was off by a tooth, If it was off by 2 or more teeth, you have catastrophic failure.


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  (#5)
TPG - screw face
 
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March 4, 2009, 09:02 AM

thanks for feedback so far...it's very helpful.

now hypothetically...let's say the cam chain was off 2 teeth, how would engine failure show itself? and how soon? the "how soon" would be applied to engine failure time from when the cam chain jumped.

the same hypothetical questions, but with the cam chain off 3 teeth....?
i can only assume the answers to 3 teeth will be much worse than the answers to 2 teeth.

what are some ways for the timing to become off? is the cam chain jumping the only option? if so, what can cause that?

finally, what can a rider experience while riding with off set timing?

thanks

Last edited by Oneway; March 4, 2009 at 09:05 AM..
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March 4, 2009, 09:10 AM

One tooth off. You can ride, it will be down on power, compression will be low, but even. 2 teeth off, depends on the engine design, 3 teeth off, I think any engine would be in trouble. One thing you may be missing is this. If you install the cams wrong, this would be the scenario. If the tensioner lets the cams jump time, the first time may be ok, the second time bends valves.


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March 4, 2009, 09:14 AM

I think if your chain was off three teeth, your valves would be destroyed... I don't think that would take long..


2008 - Kawasaki ZX-6R
2007 - Suzuki GSX-R750 (Sold)
1999 - Yamaha R6 (Sold)


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  (#8)
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March 4, 2009, 09:42 AM

now i'm not positive on the workings of the spring loaded CCT, so excuse me if i am incorrect in my thoughts.

as the cam chain spins, the spring loaded cct extends or applies pressure on the chain to keep it tight. When the cct gives out, the plunger on the spring can move ever so slightly back and forth..causing the chain to have slack? thus causing a jump...?

With a faulty spring loaded cct, can there be more than one jump? I think that would apply to a manual cct, but how would that apply to one that is, for lack of a better phrase, constantly adjusting itself?

if the cams were installed wrong, how soon would it be noticed?

can anyone confirm that if i take the spark plugs out of the bike and manual turn the motor, i would be able to feel resistance which could be a bent valve? Taking the plugs out would decompress the engine...yes?

but however, if the valves are checked and all are within spec, except for one..off by an extremely small measurement and a shim is replaced and now that valve is in spec....are my chances for a bent valve still high?
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March 4, 2009, 09:52 AM

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March 4, 2009, 09:54 AM



2008 - Kawasaki ZX-6R
2007 - Suzuki GSX-R750 (Sold)
1999 - Yamaha R6 (Sold)


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  (#11)
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March 4, 2009, 09:55 AM



my fault for caring for my bike
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March 4, 2009, 10:02 AM

Oneway,

There are times to go for it and work on your bike and there are times to fork over the cash and let the pros do it. Now is the time to fork over the cash.


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Attack Life! It's going to kill you anyway.

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  (#13)
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March 4, 2009, 10:09 AM

i've forked over well over $1500 to various pros since this problem started a year ago....i have no cash....but still have the problem

but i totally understand if these questions are too hard to answer....oddly enough....gixxer.com had no problem answering them...didn't even make jokes....so i'm just asking on here to see if the answers are matching....

but i figure this will be the end of thread...so thanks to all who answered

Quote:
Originally Posted by zx6rfool View Post
Oneway,

There are times to go for it and work on your bike and there are times to fork over the cash and let the pros do it. Now is the time to fork over the cash.

Last edited by Oneway; March 4, 2009 at 10:15 AM..
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March 4, 2009, 11:33 AM

1-Just to let you know if the valves where bent the result would be a greater valve clearance due to the valves not seating properly.
2-A cam being out of time can cause low and high compression readings. It depends on if the cam or cams are retarded or advanced.
3-It depends on the engine design and the lift and duration of the cam as to how many teeth the cam can be off before engine failure.
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  (#15)
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March 4, 2009, 11:51 AM

lol the phrase "engine failure" always gets me.

hypothetically - i've ridden with this issue for about a year now...everyday....group rides....cold..rain...hurricanes...snow...long trips...even get up to around 115mph just for poops and giggles if i'm late for work. (115-135mph is about it then all acceleration is lost) is that a timing issue?

when idling and i go WOT, the RPM needles bounces around 7-10k...is that timing issue? from what i've read...it's a common thing when the cams are out of time, is this correct?....but at idle..she purrs like a kitten

again..what is engine failure? lock up? constant backfiring? "popping spit"? as i've learned that phrase recently. Because I have experienced NONE of that ever since this happened? and i ride the piss out of it.

Last edited by Oneway; March 4, 2009 at 11:54 AM..
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