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View Full Version : Another Big Red Engine Noise Question



killerklown
08-30-2009, 07:34 PM
I just fired up a 87 Big Red that has been sitting for YEARS. I cleaned the carb, freed up the brakes, changed diff. fluid, new fuel and plug, changed the oil, and cleaned air filter.
The thing fires up with a bump of the starter button, and NO smoking. Purrs likes a kitten when I'm driving it around, and shifts smooth too.
However when idling there is a noticable clicking or ticking, I thinnk from the top end. It goes away, I suspect a little over 2000 RPMS.
From what I've read it could be valves, chain, or tensioner, or a few other rarities. What do you think would be most likely, or something maybe from sitting so long?
I've only worked on 2 strokes...

Pafrig
09-03-2009, 01:52 AM
adjust cam chain, (under little rubber boot on riders left hand side by the cylnder base. just take the 10mm lock bolt out, then loosen the 14 mm adjuster bolt. idle for a few seconds and it will adjust itself, then tighten stuff back up. #2, adjust the rocker arms. you should get a special tool for this, but a 10 mm socket, vice grips, and flat head screw driver works. sometimes.

Honda_Dude
09-03-2009, 04:47 PM
I think the 87 Big Red cam chain uses an auto-tensioner on it and there is no adjustment.

tri again
03-22-2010, 04:30 PM
I just fired up a 87 Big Red that has been sitting for YEARS. I cleaned the carb, freed up the brakes, changed diff. fluid, new fuel and plug, changed the oil, and cleaned air filter.
The thing fires up with a bump of the starter button, and NO smoking. Purrs likes a kitten when I'm driving it around, and shifts smooth too.
However when idling there is a noticable clicking or ticking, I thinnk from the top end. It goes away, I suspect a little over 2000 RPMS.
From what I've read it could be valves, chain, or tensioner, or a few other rarities. What do you think would be most likely, or something maybe from sitting so long?
I've only worked on 2 strokes...

just went thru the same thing YESterday for the last week.
Death rattle was a barnmonkey adjusted the valves
Intake lash was at least 1/4 inch.

The only hope was that the banging click as the exact same time as the exhaust pulses so I knew it had to be in the valve train, but stll kept me awake till i could get back to it.

I would not believe that a valve could sound that bad and not be suicidal, if I didnt see it for myself.

kinda hard to get to to tighten adjuster and keep the lock nut loose at the same time..so
being an evolved barnmonkey myself, I got a piece of tiny diameter fuel line from a weedeaterabout a foot long, squeezed onto the tiny SQUARE adjuster, held the locknut with a box 10mm, and was able to twist the adjuster anywhere I wanted and hold it so I could lock the nut.

Nice to be broke and despirate

purrs like a sleeping baby and starts with the shortest possible hit on the starter

BIGREDGUY
03-22-2010, 06:19 PM
Yep do your valves and how long was it sitting?

hdbowhunter
09-06-2010, 01:37 PM
How much noise is normal?Ive been away from 3 wheelers for awhile but isnt a little top end noise normal?I have a 85 250es now that had a broken crank.I ended up swapping motors instead of rebuilding.I installed a 1987 motor out of a trx250 quad.If Im correct the cam is self adjusting. Correct?It runs like a beast and doesnt smoke.I do have some top end noise but I think a lil is normal .isnt it?I had a brand new 1999 250 recon that sounded like tin cans rattling together,from day one.It was alot louder than this Big red.

300X
09-16-2010, 12:21 PM
weld a small socket onto the end of the tensioner, it usually gets wore out and can not adjust, or your timing chain guides are worn out, i've had a socket weled in mine for years never had a tick since

0GravityMX
09-16-2010, 03:19 PM
weld a small socket onto the end of the tensioner, it usually gets wore out and can not adjust, or your timing chain guides are worn out, i've had a socket weled in mine for years never had a tick since

thats the DUMBEST thing ive ever heard in my life!
why not fix the actual problem before it causes some real damage!