subaru robin eh035 problems.... help!

Discussion in 'Rack Mounted Engines' started by ballermj23, Nov 29, 2010.

  1. ballermj23

    ballermj23 New Member

    hello my name is luis i have been here for a while now. i have a 2 stoke bike for quite some time now. How ever my new subaru robin eh035 with BMP kit is making a loud noise when i accelerate.

    i would say when a give it gas.. (1-10) it make scratching noise from the circular clutch thing. I think is trying to engage. i have seen videos of same engine with out that sound.

    please help me with my new build. :sweatdrop:

  2. Happy Valley

    Happy Valley Active Member

    Hi Luis

    There might be a slight 'pinging' sound when a centri clutch engages, particularly when new during break in, but it should never last for more that a couple seconds on takeoff and not be pronounced.

    It's impossible to diagnose without hearing it so trust your judgment if you think something is wrong.

    If if were mine and I had a persistent problem that wasn't going away I would pull the engine off and inspect the parts. The clutch shoes on the engine should be fairly smooth with no scoring, free of any grit or dirt and the shoes and spring should be tight and well seated.

    engines 008.JPG

    The clutch drum on the drive side should have a smooth inner surface and no scratches or scoring and be clean and free of any debris.


    The clutch drum and bearings should also spin freely in the drive housing.

    Barring any problems seen on the inspection, then on reassembly carefully align the engine onto the drive housing and evenly tighten down the four bolts to snug. You do not need to over tighten these, the bolts are steel and go into the aluminum shroud on the engine, good and evenly snug is best. After you tighten the bolts down, check to see if the shaft/roller spins freely and everything is well aligned as it should be.

    Hope this helps and if you still have a problem let us know.
    Last edited: Nov 30, 2010
  3. ballermj23

    ballermj23 New Member

    thank you for your reply Happy Valley.

    well the engine is used... i have checked the clutch shoes and seem to have some meat. I have also taken a look at the clutch drum, it looks smooth.

    I will remove the engine again, turn it on to see if the sound persists with out the clutch drum install.

    i will try to get a video... so you can head it your self ...
    Last edited: Nov 30, 2010
  4. 5-7HEAVEN

    5-7HEAVEN Guest

    Raise the engine as high as possible. With engine not running, spin the friction roller with your hand. If any scraping noises, remove each engine bolt one at a time. Keep spinning. If noise goes away after one particular bolt is removed, leave that bolt off. If the noise went away, either the bolt is a little too long and scraping the engine. Also, either the engine OR the friction drive housing is not perfectly drilled.

    If noise still persists, remove engine. Look inside the clutch drum, see if the nut is shiny. It MIGHT be scraping on the clutch.

    If your engine is still making noise, shim each bolt with a thin washer, between engine and drive housing.

    Good luck.
  5. ballermj23

    ballermj23 New Member

    thank you for your tips... i going to try it right now.
  6. robin bird

    robin bird Member

    They naturaly make a clanging noise before engaged.
  7. ballermj23

    ballermj23 New Member

    still trying to figure it out... i really need to make a video to show you guys.

    i finish my bike and i been testing it out. it works great after the clutch engages. I have notice that i hear the loud scraping sound when is on idle!
  8. PatrickW

    PatrickW Staff Member

    Luis...Welcome to MBc. I have quite-a-few miles on my Robin-Subaru, mounted on my rather heavy Trailmate Delta Trike. Here's some advice Dave Staton (Staton-Inc.) gave me when he sold it to me along with his gear box: To prevent any 'ringy-dingy' or scraping noises, get your bike rolling by pedaling a little, stab the gas to full throttle for a second or two, then back off the throttle, and run as normal. In other words, don't try to start off from a dead stop on engine power alone. It will wear out the clutch and shorten the life of the whole engine. I have followed this advice and have never had a problem. Hope this helps.

  9. ballermj23

    ballermj23 New Member

    thanks! well i been doing that since i have had a 2stroke before, i am just use to it i guess.

    but i dont think your engine makes scraping sound while is on a STOP (idle-ling)
  10. ballermj23

    ballermj23 New Member

    well THANK YOU for all the tips guys!!!! i think i found the problem. :cool:

    1) I remove the engine and turn it on. No noise!

    2) Installed the engine with 3 engine bolts. Tightening them down in a triangle pattern.

    3) turn the engine on. NO scraping sound at idle at last!

    finally put the last engine bolt, still no sound.

    Im going to ride it to work today, will see how it does. :whistling:


    I have riden my bike to work about 15mins from my home, no scraping sound! all i hear is the clutch. :cool:

    may i add that the subaru robin motor is so quiet at idle. :tt1:
    Last edited: Dec 7, 2010
  11. lowracer

    lowracer Member

    I experienced a loud mechanical sound too after installing a EH035 onto a BMP. Turns out there was some play in the shaft/bearing area that was easily corrected by adding another washer to the end & using the end screw to pull the shaft into the bearings to remove the play. The drum was vibrating without this play removed & causing quite a racket. Be sure to be able to spin the drum & shaft easily with your fingers before re-installing everything (too much tension on the bearings will cause binding & premature wear)...