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jack grabes

2018 beta 300 rr problem: loud screeching noise!

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i have had my beta for about a year now. bought it new and took good care of it. just recently i wanted to try a track so i went with a few friends. i was riding hard almost always in power band and about 7 laps in it started making a loud screeching noise. i have no clue what this is and would like some help finding out. it has the original piston and has never been rebuilt. after the incident i didn't ride at the track any more, brought it home, and about 3 days later i took it out for another ride. again i went hard too see if it still made the noise and sure enough about 20 min in, it started making a light screeching noise. not as loud as on the track. can anyone help pinpoint this? 

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still using oil injection? If so then it may be under oiling under heavy load. Run it hard with some 60:1 pre mix (combined with your OI) and see if that reduces the noise. I'd also remove front exhaust pipe and examine piston for streaks or wear marks.

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Was the noise coming from the exhaust? Like three times noisier than normal? And engine performance suffered? Could be a stuck power valve. Mine did this. I had no idea what the sound was, but it did sound horrible. But my engine had 260 hours on it when it made this noise.  Gave it a good thrashing and the noise has not come back🤣

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Loud squeal sounds like a bearing seizing to me, and what does that?  Lack of adequate lubrication.   Hate to say but it sounds like the damage has been done.  

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the loud noise didn't come from the exhaust but it may be a lower end bearing. adding in the oil premix has seemed to work on shorter rides but i will test a longer ride in the future and see how it holds up.

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If the bearing is the cause it's toast. Likely OI failure.

 

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Wow! I guess I'm old school but if I hear a noise like that or any other that is unusual I do a thorough inspection in my shop. Wow!

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3 hours ago, Piney Woods said:

Wow! I guess I'm old school but if I hear a noise like that or any other that is unusual I do a thorough inspection in my shop. Wow!

Better to just need a new crank rather than new cases too.:thumbsup:

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12 hours ago, jack grabes said:

I will haven’t had time to take it out and test it.

Whats to test?  I assume you have little mechanical experience.  Trust us its not going to fix itself, and will come apart one way or another.  Better on your terms.

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I suggest disassembling the engine, gearbox, and/or clutch and determining the cause of the noise before doing anything else.  Riding the bike further or choosing a repair strategy before making accurate diagnosis are both guessing games at best, and may to do further damage at worst.

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A loud squeal, squeak is a a sign of metal/metal contact from lack of clearance and proper lubrication.  You should pull it down and see what happened.  You seem to be the latest victim of that wonderful, convenient Beta OI system.  Fix and mix, enjoy without issues.

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Ok. That’s what I will do. Definitely getting rid of the oi. Do you recommend the delete kit from beta or just get rid of the pump and other stuff and plug the hole in the reeds?

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13 minutes ago, jack grabes said:

Ok. That’s what I will do. Definitely getting rid of the oi. Do you recommend the delete kit from beta or just get rid of the pump and other stuff and plug the hole in the reeds?

Either will work.  The OI Removal Kit gets you a new intake manifold with no oil port and a little plug if you choose to remove the TPS from the carb to achieve a little lighter pull on the throttle.  These OI Removal Kit Instructions are a good read for the steps, even if you don't opt to use the kit.

If you don't use the kit, you'll basically do the following:

  1. Disconnect the oil pump electrical connector. At this point the ECU will detect the missing pump and illuminate the OI "MIL" light on the speedo whenever the bike is running.  You can ignore the warning light or, If you're committed to using premix, you can clip the pink wire with purple stripe shown in my image below for 2017 and newer bikes. (Note that the wire removal method discussed in the OI removal kit instructions is for 2015 and 2016 bikes, which use a different speedo with different connectors.)
  2. Disconnect the oil tank level sensor electrical connector.  This will prevent the "low oil level" warning light from illuminating.
  3. Disconnect the oil line from the intake manifold oil port. It's up to you whether you completely remove the oil line, or just cap it off.  Some just kink it back on itself and secure with a zip tie.
  4. Plug the oil port in the intake manifold, or install a new manifold with no port. If leaving the original manifold in place you can cap it with a vaccum cap and zip tie, or by using a short piece of oil line kinked and secured.  The objective is to plug the port and prevent air leak into the intake manifold. 
  5. Drain and/or remove the oil tank. (Doesn't hurt anything to leave it in place.)
  6. Mix up some premix and ride. Pre-OI Beta's were recommended to use 60:1.  I've run both 40:1 and 50:1 with great results.

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Although a bit pricey, I'd get the kit, no chance of a manifold plug coming loose then.  We did this to my neighbor's XTrainer, you also get a plate to delete the TPS.   Pull all the other junk from the airbox and harness and make it like it was never there.

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On 11/5/2018 at 8:07 AM, jack grabes said:

Do you recommend just doing a bottom end rebuild? And top end

Pull the plug, pull the flywheel cover, put a wrench on the flywheel and turn it. Report back.

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On 11/5/2018 at 8:28 AM, GP said:

 Fix and mix, enjoy without issues.

:lol:

The RE's come with the OI removal kit already installed; a $127 value! :thumbsup:

New motto:

"Us 2t smokers would rather ride than fix"

Edited by Bermudacat
Ride sub for mix cuz I like it better
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