Death Rattle on Start-Up

[free2ride]

80 K with 80k [how interesting!].

Anyway, when I start the thing up cold there is a rattle in the engine for a minute until [I think though I'm no mechanic] oil flows and lubricates things. If I'm right in the diagnosis, is this normal? If I'm wrong, any ideas?

[Re-run]

Hard to say. I would say do a tuneup and get the carbs synced. Maybe check the clearances on your oil pump to make sure it is not out of spec.

[OTTODOCTOR]

You didn't mention what oil you're using , but it sounds like possible bearing insert problems . -- 80k is a bunch of miles , depending on the upkeep it's had. -- Clearances are probably excessive , and the rod bearings rattle until the oil pressure comes up . -- Test your oil pressure with a gauge tapped into the sending unit port , and compare it to the specs. in the manual . -- Probably low due to excessive clearance . -- Good luck .

[rm56]

Could be loose valves or your timing chain is streached out and about to get eaten. Loose valves will clack loudly if they are not adjusted right. A loose timing chain will slap against its guide and make a lot of noise also. 80K miles unless the bike had regular oil changes (I doubt it) is a million miles for old Hondas, overdue for overhaul. You have a double overhead cam engine. The top ends on those had issues. Thats one reason I bought a SOHC. My engine has 20K original miles, I keep it adjusted change the oil on time. It can go 300K if taken care of, can't say that for the later DOHC engines. Just not as bulletproof IMHO.

[free2ride]

I'll have a winter to explore [or get exporation done for me].

fwiw, the engine was just ripped apart, new bearings installed, everything adjusted, pressure good.

I doubt very much how regularly the oil was changed before I got it -- but I look after that now!

[OTTODOCTOR]

This information would have been helpful . -- Without actually hearing the noise , I still suspect a clearance problem . -- My field of (expertise?) is automotive , but I've built hundreds of engines in my 37 years . -- As an engine builder , if there is a noise in one I put together , I want to know what it is . --- If you can contact the engine builder , he may feel the same as I do about his work . -- Worth a try anyway . -- Best of luck to you in your endeavors . -- Otto

[Re-run]

This is why you do the tune up spectrum. It eliminates all the simple common causes. Always start at the bottom if you do not know what the problem. Would you rather adjust your clutch or tear apart the tranny?
Besides, many issues are simple things easily fixed.

[woodsrider250-2]

Properly maintained DOHC motors have routinely seen over 100k and more.  Have to stay on top of the shims, and cam chain.  As shims wear, clearance goes away.  The SOHC's are easier for sure, but don't know about more/less reliable.

[Re-run]

Yeah I wouldn't say the dohc is bad by any means. More complex but it is dual cammed. All about the preventive work.

[OTTODOCTOR]

Does this noise change if you pull the clutch in ???