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Top end noise after engine assembly

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A s bike we had had a bad bearing in the transmission so I found an e bottom end and assembled the engine using the e bottom end and the s cylinder, and complete head from the s. I used an e base gasket if that matters.

I never heard the bike run before it was disassembled but I can't imagine the noise was present then. Well I pulled the valve cover of and set the engine to top dead center. One of the intake valves is in spec and the other 3 valves are too tight (under spec) how would that cause valve noise?

I've researched top end noise on drzs and its pretty consistently valve noise. I've also confirmed it with a stethoscope. So is there anything that could cause the noise? I've heard of valve clearances too loose that cause noise bur never to tight. Now I've ordered shims and will correct the clearances but I'm just curious if there is other possibilities. All the can surfaces and lifter surfaces look mint too. Nothing abnormal.

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Too tight as no clearance at all? but no, the noise is extremely unlikely because Of a tight valve lash, unless the valves are so tight they are hitting the top of the piston.

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Does it have the decompression mechanism? My E has it still but it is clicking really bad. I need to take it out as it has a loose pin that can almost come out.

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My smallest feeler gauge won't fit between the cam and the lifter.. Its .127mm.

Also, it does have the decompression mechanism. Any threads on removing it?

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I'm sure there is info somewhere around here. I haven't removed mine yet but I know it has been done.

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Valves that are too tight are ones where the valve is receding into the head (towards the cam), and are thus even less likely to be hit by the piston.  So unless one places hugely large shims under the buckets, it is not likely.

 

 

So things to check for top end noises in order of importance:

 

1) Make sure oil is being pumped up to the head - usually easy to tell visually

2) Ensure the cam caps are installed correctly and evenly tightened

3) Make sure the valve timing is correct - follow instruction on this site (it will run, though not well when one tooth out).

4) Cam chain tensioner - follow instructions on this site (this can and does make a lot of noise)

5) Set all valve gaps to within spec - go and get decent set of gauges that can measure between .1 and .3 millimeters.

 

The audio clip is not clear enough for me to discern much - but if i had to guess I would guess cam chain.  Our bikes are very noisy.  I still get paranoid over it.

 

 

Too tight as no clearance at all? but no, the noise is extremely unlikely because Of a tight valve lash, unless the valves are so tight they are hitting the top of the piston.

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I've checked torque on the cam caps, timing is correct, I've also swapped in another acct and nothing changed. I haven't verified that I'm getting oil to the head though. How could I verify that? I mean when there valve cover is off there's oil up there but that's not an indication of pressure really

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Well I re-shimmed the valves and got the clearances to .15 and .17 on the Intake side and .26 for both on exhaust side. The noise is significantly less but is still there. When using the E base gasket how much clearance is there from the valve to piston. That's the only thing I can think of. Oh and the decompression mechanism is removed too.

Note- if you have a "high compression" engine with an E base gasket and the decomp removed it will be nearly impossible to start the bike with the stock battery.

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How many miles on the S head, piston and barrel?

The original engine had done enough for a bearing to fail in the gearbox, why wouldn't you give the top end a freshen up if your going to go the trouble of swapping those pars over?

Or do you plan on selling it to some unsuspecting buyer?

Depending on how tight the valves were, it may have burnt a valve, that will give you a ticking noise.

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How many miles on the S head, piston and barrel?

The original engine had done enough for a bearing to fail in the gearbox, why wouldn't you give the top end a freshen up if your going to go the trouble of swapping those pars over?

Or do you plan on selling it to some unsuspecting buyer?

Depending on how tight the valves were, it may have burnt a valve, that will give you a ticking noise.

around 4k miles on the s engine parts (head, piston and cyl) . It was ridden on the highway at WOT every day which I would believe did the bearing in. The top end looked good as far as wear surfaces and such, nothing out of the ordinary at all. No signs of burnt valves either. Well, nothing obvious, but I didn't really look at the valves with a fine tooth comb though. and no I don't plan on selling the bike. and it was only run very minimally with the valve specs tight; less than 5 minutes. 

Edited by SupaDupa_Steve

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Ok so after a MCCT and double checking everything I've decided to pull the head. What should I look for? I'll probably swap it with another head to see if the noise goes away but what should I look for as to what is causing the noise? 

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