99 GSXR 750 CamChain slipping?

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99 GSXR 750 CamChain slipping?

All,

My exhaust cam had slipped a few teeth resulting in no compression, not firing etc, anyway;

Bike is a 99 GSXR 750 WX with 25k on a standard engine

I'm not a bike mechanic by trade but managed to strip the engine down and reallign the exhaust cam,

fired up 1st time after but sounds a bit rattly

Does anyone know what is needed to fix this problem permanantly,

new tensioner? New Camchain?

Anyone know a good mechanic near SW London?

Call me on 07900 60 50 40

If it's slipped 'a few teeth' I'd be very surprised if Mr. Valve hasn't given Mrs Piston Crown a good hard wallop Are you sure it was out - marks not lined up, wrong number of pins between marks?

i lined up the timing mark on the bottom crankshaft and you then have timing marks on the inlet and exhaust cams that have 1-2-3 on them.1 should be at 3 oclock on the exhaust cam,2 should be at 12 oclock on the exhaust cam3 should be at 12 oclock on the inlet cambasically, 2 was at 1 oclock on the inlet1 was at 4 oclock My initial symptons were not firing, at all, even tho we had spark and fuel.I realigned the exhaust cam but it sounds a bit loud now, it runs, but doesnt sound right

i personally wouldn't turn your engine over till someone with a bit more experience has looked at things as it sounds like you have possibly mis adjusted the timing if the noises are worse than when you started and if you're really unlucky mr valve and some of his brothers are in need of replacement ....also if the valve timing was genuinely out before you adjusted it i'll expect it to need new valves anyway ....the only time i ever put a camshaft in wrong was in a cb350K4 (circa 1974 ish), i put that in 180 degrees out but survived it

The marks can look out if you look with the tensioner removed as this allows the cams to be moved by the action of the valve springs pushing against them. On Suzukis there's usually a certain number of pins of the camchain that have to be counted between the #2 and #3 marks on the cams - like this ....... this is from a 600 - your's may be different. Check!As nitemare says, I've seen bent valves from them being installed only two pins out and then the engine turned over.

Pretty much as everyone above has stated. The only reason it would have jumped a couple of teeth in the first place is tensioner failure. If, after retiming as per the book and replacing the tensioner, it still sounds wrong / cronic loss of power etc then it's a case of firstly checking the valve movement. Assuming it's timed up correctly, turn the motor over by hand, checking up and down movement of the buckets and checking clearances. If inconclusive, whip cams out and manually check for up and down movement on each valve, ensuring relevant piston is not at tdc when you do it. Would imagine there is damage and you'll have to pull the head off and replace what's broke/bent. If you're lucky it''ll be a couple of valves and only a slight kissing mark on the piston crowns but it all depends on whether you were hammering down the motorway at 150mph or just trying to start it when the tensioner failed.

Thanks guys, blinding info.The exhaust cam had definatley slipped, because I had left the tensioner in place whilst I examined the cams, they where definately out of line.I never had the luxury of them 'wire clamps to keep it all in check whilst i tightened the cams down.Anyone near SW London fancy a rebuild?I'll keep you updated of course.Andy

wiggetta wrote

Thanks guys, blinding info.The exhaust cam had definatley slipped, because I had left the tensioner in place whilst I examined the cams, they where definately out of line.I never had the luxury of them 'wire clamps to keep it all in check whilst i tightened the cams down.Anyone near SW London fancy a rebuild?I'll keep you updated of course.Andy

as others have said they dont just "slip" either the tensioner system fails, cam chain breaks or there is a catastrophic failure elsewhere in the engine.

im with FF on this, i doubt its slipped. Now way a GSXR motor is surviving that, timing is too close. A Ford pinto you gewt away with it, a GSXR, naahh.Kev

KFZ wrote

im with FF on this, i doubt its slipped. Now way a GSXR motor is surviving that, timing is too close. A Ford pinto you gewt away with it, a GSXR, naahh.Kev

We had a gsxr that DID slip. The guy started it up one morning heard a nasty noise as it was turning over on the battery. Tried to start it again and it fired up but was rough as hell. We couldnt believe it when we saw it and we were expecting broken valves and everything..Obviously this is VERY VERY rare but it has happened.

G, as you said, if it jumps a single tooth on start-up then you'll probably get away with it, a few teeth and it's goodnight vienna. We've had a couple of bikes come in where the customer has changed their own tensioner and not checked the timing before start-up. The SRAD almost always jumps a tooth as soon as you remove the old tensioner, so the only way to do it is to keep the tension on the chain from the top of the engine and recheck the timing before you start it up.Btw Wigetta, those wire clamps that Suzuki are talking about can be substituted by zip ties.

prilla wrote

G, as you said, if it jumps a single tooth on start-up then you'll probably get away with it, a few teeth and it's goodnight vienna. We've had a couple of bikes come in where the customer has changed their own tensioner and not checked the timing before start-up. The SRAD almost always jumps a tooth as soon as you remove the old tensioner, so the only way to do it is to keep the tension on the chain from the top of the engine and recheck the timing before you start it up.Btw Wigetta, those wire clamps that Suzuki are talking about can be substituted by zip ties.

You saying it jumped the sproks as the old CCT was removed, engine not running of course? Would seem to make more sense.Kev

KFZ wrote

You saying it jumped the sproks as the old CCT was removed, engine not running of course? Would seem to make more sense.Kev

I wouldn't fancy removing the CCT with the engine running Sorry if I wasn't clear, both customers had changed their CCT's as their bikes had been running fine but were rattly. After changing the CCT's, the bikes ran as rough as f**k. Bikes had jumped a tooth as soon as the old CCT's had been removed. (Old CCT out, jump, new CCT in) It's common on the SRADs, the Suzuki forum even had it as a sticky as loads of people were getting it wrong.

Just thought I would update you guys after all your fantastic info.Let me tell you full story.1. Bike running fine2. Started up 1 morning, loss of power, felt like it was retarding (ignition/fuel)3. Stripped the bike, changed plugs, oil, filter (basic stuff, I'm not a mechanic!)4. Started up, ran ok an idle, still no power5. Started up next day, nothing, no fire, just bobbling along whilst cranking, bugger 6. Called up a mechanic, he led me down the route of timing, cams etc (Optimax, great guy)7. Bought a Haynes manual and tested every single sensor on the bike that could effect timing (Crank sensor/Throttle Pos Sensor/ Gear sensor/ etc etc) all checked out ok8. Decided to check out the cam positions as a wild guess, bearing in mind I'm not a mechanic this is a very new thing to me 9. Took off the engine cover and found this As you can see, the #1 mark should actually be in line with the engine casing, not above it like it was10. Bought a new cam chain tensioner as I had researched that the 99 750 had a recall for it's poor tensioner(I Have enclosed a video of my old tensioner out of the engine, can anyone confirm that you should be able to push the tensioner back into itself whilst locked? I was under the impression it locked itself and would not move back inwards? www.ifitstuff.com/images/bike/cam_chain_tensioner.AVI )11. Got my workshop ready, including the print out from FastFitter (thanks ) took apart the engine Very scary to a newbie12. Took out the old CCT and rotated the cams into line by using a screwdriver and a rubber mallet 13. Counted the teeth, used a couple of cable ties to hold it all in place and inserted the new cct.14. Reassembled the engine and fire it up, bang, 1st time fired, ran sweet as a nut, no rattling, no probs.15. Took bike out for a spin, WOW , it's on song, revvs perfect, power is perfect, I'm very very happy.........Many many thanks to all the people who helped me with this problem, it had me sad, glad, stressed, confused..... I appreciate I have been very lucky with this, as I realise I could have ended up with a busted engine.Can't wait to meet up for a ride in the SW London area soon, :smoke:

wiggetta wrote

Just thought I would update you guys after all your fantastic info.Let me tell you full story.1. Bike running fine2. Started up 1 morning, loss of power, felt like it was retarding (ignition/fuel)3. Stripped the bike, changed plugs, oil, filter (basic stuff, I'm not a mechanic!)4. Started up, ran ok an idle, still no power5. Started up next day, nothing, no fire, just bobbling along whilst cranking, bugger 6. Called up a mechanic, he led me down the route of timing, cams etc (Optimax, great guy)7. Bought a Haynes manual and tested every single sensor on the bike that could effect timing (Crank sensor/Throttle Pos Sensor/ Gear sensor/ etc etc) all checked out ok8. Decided to check out the cam positions as a wild guess, bearing in mind I'm not a mechanic this is a very new thing to me 9. Took off the engine cover and found this As you can see, the #1 mark should actually be in line with the engine casing, not above it like it was10. Bought a new cam chain tensioner as I had researched that the 99 750 had a recall for it's poor tensioner(I Have enclosed a video of my old tensioner out of the engine, can anyone confirm that you should be able to push the tensioner back into itself whilst locked? I was under the impression it locked itself and would not move back inwards? www.ifitstuff.com/images/bike/cam_chain_tensioner.AVI )11. Got my workshop ready, including the print out from FastFitter (thanks ) took apart the engine Very scary to a newbie12. Took out the old CCT and rotated the cams into line by using a screwdriver and a rubber mallet 13. Counted the teeth, used a couple of cable ties to hold it all in place and inserted the new cct.14. Reassembled the engine and fire it up, bang, 1st time fired, ran sweet as a nut, no rattling, no probs.15. Took bike out for a spin, WOW , it's on song, revvs perfect, power is perfect, I'm very very happy.........Many many thanks to all the people who helped me with this problem, it had me sad, glad, stressed, confused..... I appreciate I have been very lucky with this, as I realise I could have ended up with a busted engine.Can't wait to meet up for a ride in the SW London area soon, :smoke:

well done to that man!! See its not rocket science.Next time before you start just turn the engine over by hand, make sure its going to be ok.You did good!Kev

wiggetta wrote

I Have enclosed a video of my old tensioner out of the engine, can anyone confirm that you should be able to push the tensioner back into itself whilst locked? I was under the impression it locked itself and would not move back inwards?

I've not played with an SRAD donkey but on other Suzi lumps you undo the locknut/screw, push the tensioner fully home and then tighten the locknut. This holds it 'loaded' until you bolt it to the engine, then release the locknut which allows the tensioner to spring forwards and clout the chain runner blade thingy, taking up the slack.Nice pics and a well organised workbench - fags at the ready No sign of a mug of tea though, you still have much to learn Wigetta As Kev says, that took a bit of bottle diving in there but if you adopt a methodical approach and don't panic tha'll be reet :smoke:

Well done matey. As Kev said, once you've timed it up it's always a good idea to turn the motor over a couple of times by hand (spanner on the end of the crank) to confirm it's timed up properly. Stops you having to wince when you hit the starter button. Just watched your CCT video......... that's donald ducked alright.

A mate with a GS thou once couldn't wait for me to nip round and give him a hand - he got the cams back in a couple of teeth out. When I got there he said he'd turned the engine over with a spanner. "It was a bit stiff but it went eventually but with a bit of a 'clang'."Four valves bent

wiggetta wrote

2 was at 1 oclock on the inlet1 was at 4 oclock(

By my reckoning they've missed the piston...perhaps two or three teeth out.Opening late so the pistons already on its way down.Closing late so the mixture hasn't been fully compressed.Probably just time for the flame front to blow passed the valve as its closing.Fingers crossed

I cannot actually decribe what you guys have actually done for me??You have given me the confidence to crank engines with a back wheel in 5th to count teeth, to chisel cams with rubber mallets to basically wrench a Jap tuned box of Frogs by parameters that Mr Suzi Whozi Poozi didn't equate for.I had an unfounded confidence and you guys backed me up.Here's for the underground Suzi Cam Wreckers

There's no real magic in multi-cylinder engines, after all they're screwed together by little old Japanese grandmas at the factory. Read the manual, study the pics, double check and Bob's yer whotsit.The old gits on here have tackled most jobs over the years and found ways round various problems. It might not be in the manual, and Kev might do one job different to Druid or Maddog, but if we've found a way round it we'll share it if needed.Always best to ask first though Brakes next?

done the brakes, I also put my original exhaust back on, I actually prefer the way it sounds and makes the bike feel, strange eh?

wiggetta wrote

done the brakes, I also put my original exhaust back on, I actually prefer the way it sounds and makes the bike feel, strange eh?

No not really, gut feelings are normally right, if the bike feels like its running better then it probably is... Nothing more tiresome on a long journey than a loud pipe... normally does nothing for the power delivery unless its set up right either.Kev

that's what I found, the noise was quite comical for a bit, but the bike definately has more power low down in the rev range now with the standard can back on.Race cans are obviously great when they are set up with a power commander and you spend most of your time above 7'000 rpm, mine wasn't and I don't.

NiteMare wrote

i personally wouldn't turn your engine over till someone with a bit more experience has looked at things as it sounds like you have possibly mis adjusted the timing if the noises are worse than when you started and if you're really unlucky mr valve and some of his brothers are in need of replacement ....also if the valve timing was genuinely out before you adjusted it i'll expect it to need new valves anyway ....the only time i ever put a camshaft in wrong was in a cb350K4 (circa 1974 ish), i put that in 180 degrees out but survived it

I did the same thing on a 1968 CL350 the sprocket could go either way (180 out) wouldn't start but no damage, once I figured out how move the engine to get it in and out of the frame it was easy.

has anyone actually taken a failed camchain tensioner apart to see how exactly it has failed...a broken spring perhaps, could they be repaired, upgraded, with a better spring...interested to know as I have just bought a low mileage 99 srad 750...already have a brand new good quality manual tensioner in case it is needed...but would still want to take apart the standard tensioner to see if that could be fixed somehow, as continually having to adjust a manual tensioner would soon become tedious I think.. let me know. Paul   paulisg998@gmail.com

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