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Decompression Starting Problem

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3 yrs back I did the 465cc BB/stroker upgrade and E-base gasket and found that the standard battery wasn't enough to start the engine. I did the R1 battery conversion and had no problems starting at all. 3 times, had to re-shim the valves for clearance issues with no problem, BUT after the 4th time the electric starter started to have problems. I changed out the alkaline battery for a Shorai Li-ion battery but still had the same problem. Replaced the valves AND fitted a kick starter (for emergencies) but the same problem still exists AND the kick start is almost impossible to kick through

 

I can only describe the cranking sound like the battery isn't powerful enough (but its at full power!)

 

My mechanic swore it was a compression problem, so I switched back to the standard 3 layer base gasket, but the problem is still there during cold and hot starts. I would assume that when cold starting, compression shouldn't be the issue

 

The starter clutch was 'free-wheeling' for a short time, so I took it off, gave it a bit of love and the loc-tite fix as 3 of the 6 bolts were loose, now it seems to be fine and not free-wheeling

 

This only happened since the 4 time the valve clearance was done, so I can only assume its an issue at the top end.

 

Has anyone ever had/heard of parts being restricted in the top end (cams, chains, guides etc) that could cause this? I've investigated as much as I can and can't see anything dragging. Could the starter clutch be the cause?

 

I have got the de-comp valve kit that came with the E-kick starter, but need to get the the top-end machined to fit it. This is gonna be a pain in the a**e and I don't wanna waste my time and money just to find out that its not the problem

 

I find it hard to believe is a decompression problem as it only came about since the 4th valve clearance. Is there any real way to test if top end compression is the cause?

 

Frustrated and running out of patience rapidly!! :banghead:

 

 

 

 

 

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I have a 434 with e base gasket and no decompression. I use the big 14ah Shorai and it won't crank it either. Kick starting it is impossible ever since I lost the decomp. Normally I just keep pressing the button until it catches. I really don't think there is much you can do about it. I do find it odd that sometimes it will randomly crank fine and I can get it to spin over with the kick starter but most days it freezes up when it hits compression. Kinda makes me nervous

Edited by Gsxrstuntdrz
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If it happened exactly when you did the valves and it has not started since then perhaps look over the cam timing AND if it still has an ACCT (auto cam chain tensioner) was it properly reset?  If either a ACCT or MCCT is installed improperly that will be a lot of extra drag.

 

If it happened slowly in the last while, some have indicated that once the starters start to get tired the current draw goes up but less power is produced.  The starter might get hot fast.

 

Electric and kick together?

 

Push start?

 

I don't suggest this for anything other than a few seconds of running to do a few start attempts but shim one exhaust valve a bit tight so it does not close to simulate the decomp.  0.2mm or something like that? 

 

It isn't flooded is it?  Extra fuel/liquid isn't compressable and will raise the effective compression.

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Had a similar problem with my 470 stroker. Remove your starter and disassemble it and clean the comuntater

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Thanks all for your feedback thus far

 

I had considered if it was the starter that was at fault, so that will be my next area of investigation

 

It was literally an over night problem that just appeared instantly after the 4th re-shim, not slowly

 

All cam chains, guides, and auto-tensioner checked, but no noticeable drag or resistance there

 

I was wondering if anyone had any issues with Web-cams (or any high-lift) dragging on the somewhere in that area?

 

I have tried the kick and elec-start together and it works, but Im sure as you well know, that the need to find the real answer is much more important than an improv. As for the push start, thats only for emergencies and I don't wanna even think about starting it like that on a hot and humid Tokyo morning

 

Actually, I didn't consider flooding and that could be part of the issue. I used to use the '3 squirts cold and 1 squirts hot' start technique (recommended for Mikuni TMR40), changed to the 5 squirts cold and 3 squirts hot recommended in the Drz-E kick-starter instruction book. I will deffo check that out, but that still doesn't answer the impeded cranking issue

 

I use my bike everyday to and from work and I know that the mods I have done aren't really made for 'commuter' use, but I get a chance to ride it everyday and don't mind the wear and tear. So far, I've managed to get it started every morning, but its always a worry

 

(Shorai battery is also 14 series)

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I have 2 starters. One is ready to go when the other one starts to get tired. It seems I get around 10000km's per starter

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Had a similar problem with my 470 stroker. Remove your starter and disassemble it and clean the comuntater

 

 

+1

 

as  this is the most obvious repair that is needed. once the comm starts to corrode/wear, it accelerates its wear quickly. while it may not be apparent today that there is an issue, tomorrow it seems like the bike is hydrolocked. that's how electrical problems present themselves. or intermittent.

 

clean contacts between the all the electric connections (starter BUTTON, relay, pos/neg battery, ground, commutator, etc) makes a huge difference in starting, charging, and running of the engine. 

 

and it's a free fix. 

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I've gotta wait til next month for the machining for the decamp valve, but will be sure to get back and update asap

 

Will take the starter out and clean it up and see it makes a difference, but by the sounds of the feedback, its the decomp thats the main issue

 

The only thing is, I'm still completely at a loss as to how this came on so suddenly

 

Thanks for your advice

Edited by dr-z465

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I've gotta wait til next month for the machining for the decamp valve, but will be sure to get back and update asap

 

Will take the starter out and clean it up and see it makes a difference, but by the sounds of the feedback, its the decomp thats the main issue

 

The only thing is, I'm still completely at a loss as to how this came on so suddenly

 

Thanks for your advice

 

Valve adjustment is changing the cam timing...

More valve clearance means valves closed longer , means less overlap , means more compression , means harder on the starter motor..

You get what I mean..... :)

Edited by Craigo 485sm
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Valve adjustment is changing the cam timing...

More valve clearance means valves closed longer , means less overlap , means more compression , means harder on the starter motor..

You get what I mean..... :)

 

Right, now that makes sense

The mechanic that did the valve replacement and re-shimming told me that that he had given a larger clearance this time because the valves were wearing pretty quickly. I was aware of this and there was an exaggerated tapping from the cams. He also said that with high lift cams, the clearance should be more than the standard cams. I checkered and the exhaust were at .30 and intake were at .60 . I re-shimmed the intake to .50 and it did seem to start and run a bit easier, but its still having a bit of trouble

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Why should there be more clearance?  The clearance is applicable when off the lobe and more means the valve comes off the lobe a bit sharper further up the transition and hits a bit harder on the seat I think, no?  Certainly not information I am familiar with so I am curious.

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Should I correct the valve clearance to the Suzuki recommended .20 - .30 intake and .10 - .20 for the exhaust or leave them with a larger clearance as recommended by my mechanic?

Anyone have any thoughts on this?

Edited by dr-z465

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Should I correct the valve clearance to the Suzuki recommended .20 - .30 intake and .10 - .20 for the exhaust or leave them with a larger clearance as recommended by my mechanic?

Anyone have any thoughts on this?

 

On my stroker I would run the minimum clearance on all valves  , I suggest maintaining your clearances within spec ....

If your valve specs are closing fast , it's time to pull the head for valve replacement/inspection

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I just replaced the valves. Are you saying to get the head reported even though its only done 12,000km (4000km on since BB/Stroker)?

Seems a bit early for that, no?

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Should I correct the valve clearance to the Suzuki recommended .20 - .30 intake and .10 - .20 for the exhaust or leave them with a larger clearance as recommended by my mechanic?

Anyone have any thoughts on this?

its .10-.20 intake and .20 to .30 ex
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I just replaced the valves. Are you saying to get the head reported even though its only done 12,000km (4000km on since BB/Stroker)?

Seems a bit early for that, no?

 

 

Mate , I based my response on what was said here...

The mechanic that did the valve replacement and re-shimming told me that that he had given a larger clearance this time because the valves were wearing pretty quickly.

Edited by Craigo 485sm
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