This one is for E. Marquez or Noble.

To make a long story short. Had a stroker motor built by Eddie, +4 stroke and new crank bearings, already had the big bore Only 1000 miles on it. RHC 187 cams, big valves, head ported, and 41 fcr carb, also mrd/sws pipe. The motor started on the first crank, idled fine, checked fluids and went for a ride. In 4th and 5th gear i noticed a noise that sounded like something was loose on the motor mounts or the chain slapping on something, only on acceleration as soon as you let off it stops or when you pull in the clutch it also stops. When you are crusing in 4th or 5th at 3800 to4500 rpms with the throttle just open enough to cruise the churping is there, don,t seem to notice it in 1st or 2nd, some times in 3rd. Checked every bolt on the bike and also took off everything that the brive chain could touch. Put the bike on a jack and ran it no noise applied the rear break to load the motor and no noise.Changed the oil at fifty miles, it looked find. Took of valve cover, valve clearence was fine, looked at timing chain pushed on valve springs, everything looks fine. This is driving me crazy, the bike runs fine but i spent alot of money on this project and i don't want to screw things up. Need some suggestions on what to look for.

Shouldn't this question be headed "This one is for Eddie" ?

Are you sure it is not simply the airbox chirping ? With all those extra CCs and bigger valves your engine is drawing a lot more air.....

Just side note, I never thought it was a good idea to call for help from specific individuals. I appreciate the confidence but you can not really predict where the best help will come from.

As it is, I'm stumped with your question. I would help if I could but it sounds to me like this is a hands on problem. Try having some one ride next to you or some one you trust ride the bike for another opinion. Maybe put it on a dynamometer and listen for noises.

Can,t tell where the sound is comming from, when you lean over the bars sounds lile it is under the tank. At 3800 to 4500 rpms don't think it is drawing a lot of air. Eddie is busy with a lot engine work, this is my problem to solve.

Thanks Noble,, don't you think that if it was on a jack it would be the same as a dino. It is at a very low torque situatition and the bike is so loud you can't here.

Are the cams new? Did they come with a break-in procedure? Common break-in for cams is to not let the motor drop below 3000 rpm for 30 min. Start it, immediately keep the RPMs up, ride it. You can to the heavy throttle roll on break-in for rings at the same time just keep the motor above 3000 to prevent scuffing the cams. After 30 min the rings and cams should be good to go.

'churping'? Do you mean 'Chirping', like a bird sound? If so, that is normal, it is a sound the vacuum release plate makes. I bet this is what you are hearing.

You can also get a metalic sound that is chain whip that could be what you are describing, also normal. Occurs under load at lower RPMs.

I agree, I do not know how you hear motor noise over the exhaust.

I guess you could kind of simulate dyno with the bike on a stand 4 or 5th gear and light brake to simulate cruse.

I once rebuilt a Toyota. On initial start up it had a bad knock when idled down. As long as the revs were up it was fine. The knock disappeared and I drive it about 40,000 trouble free miles. Some times you just never know.

William One,

Yes chirping my mistake. it can't be the chain took off everything that the chain could come in contact with, vaccum plates, i don't know what you are talking about? It also doesn't seem to increase with the throttle slightly increased, like it was related to rpm increase. Years ago i had a 750 honda four cylinder when i would go down a cobble stone street or cross railroad tracks the front caliper would rattle, similiar sound. Checked everything for being loose.

The vacuum plate is part of the FCR. It enables the slide to move freely and not become stuck under high vacuum. Perfectly normal.

Chain whip will happens on nearly any bike with long travel suspension, new chain., adjusted properly. It is not a sign of anything wrong, just an oscillation that occurs under certain conditions. It too, is somewhat of a chirp though it also tends to have some 'ringing' aspect to it.

To make a long story short. Had a stroker motor built by Eddie,

Step one would have been to contact the engine builder for his 2c...

As others have mentioned the chirping could be just carb related....

Step one would have been to contact the engine builder for his 2c...

As others have mentioned the chirping could be just carb related....

To be honest, thats why I did not respond when i first noticed this thread.

If one of my folks had a suspected issue with one of my builds, I would hope they would contact me first.

If you have done that and want some additional opinions, happy to help.

Get a video with good sound, that will help with internet forum diagnosis.

After my first ride i emailed eddie about my problem, no reply. I don't think he is happy with me after three months of reasons why my motor was not finished, i had a bad day nothing went right for me. I called him and got a little nasty with him and he said he was waiting for new valves because the coating was comming off of them. I later called him and appoligized to him after i cooled off. Just don't want to bother with epic any more. I thought i would ask the forum for advice because eddie has built a lot of stroker motors for them and maybe someone else had the same problem.

Chirping is normal with an fcr.

Calling me is always the most direct option if contact. If im not on the dyno or on another line im always available during business hours.

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