Beta Techno engine noise

car.davies · Post by **car.davies** » Wed Oct 24, 2007 10:16 pm

I have recently purchased the above bike, a 98 model. It has been lovingly maintained by a competant person, however the latter ends with me. I have been listening to the engine noises both under load and in neutral, indoors and out and am getting worried. I have noticed the noise of the gear box and am curious if it should be loud. I'm sure the gear box oil needs changing also. I have also taken of the head to check in there and noticed that the head plate was covered in a thick black gunge, the piston also. Should this be there and should I clean it off. I'm in need of some encouragement and advice as I'm only just getting tuned into the noises and jerks and quirks of the bike. All advice would be greatful.
Cheers Davo :shock:

Post by **David Lahey** » Thu Oct 25, 2007 6:33 pm

Davo
That thick black goo is a byproduct of combustion that needs to be removed periodically from where you have noticed it and also from the exhaust port and the inside of the exhaust pipe.
There are a few other things worth doing while you have it apart for the decoking.
Inspect and measure the piston and rings and decide of it needs new rings or a new piston.
The noises your Beta makes may be completely normal. You should be able to hear:
Gear whine as the load comes on and off the primary drive gears.
Clutch plate rattle with the clutch disengaged.
Gear rattle with the gearbox in neutral and clutch engaged.
Piston slap at idle and maybe at higher RPM.

Have a listen to a few other Technos if you are still worried about your noises.

David Lahey

car.davies · Post by **car.davies** » Thu Oct 25, 2007 9:51 pm

David,
Thanks for the responce. I have removed the coke off the piston, however I am unsure how to remove it from the port and exhaust. I am also not sure how to measure the piston and rings or what to look for if they need replacing. As for the noises, I have check for the ones you mentioned and they were spot on. I'm afraid I don't know anyone with a Techno. In fact I don't even know anyone with a trial bike here in Wagga. I'm on the move again to Darwin ( defence member ) and already have another post looking for riding partners up there. It all sounds a bit grim, but I am going to keep at it. The trials of trialing. Sorry, obvious pun. Anyway cheers for the help.

Davo

car.davies · Post by **car.davies** » Mon Oct 29, 2007 11:35 am

Ref the above job. After cleaning the head, I took it for a test run. After I had stopped, the piston ceased in the barrell. I then had to completely strip it down and to avoid splitting the engine, I spent three hours and a whole load of wood and clamps to remove the piston from the barrel. I then had to completely remove all the coke, and there was a load of it, to inspect the relevant parts. All was well. However, after some consultation with Dave from Beta racing, I found out that I was not only using the wrong fuel, but also the wrong oil and mix. I believe the best oil to use is a Motul 800 at a 70:1 mix and good high oxtane fuel. I was using shell synthetic oil and plain unleaded at the wrong mix. This woild explain the large amounts of carbon and the initial problem. I have yet to start the bike as I am awaiting some oil, but I will see what happens.

car.davies · Post by **car.davies** » Sat Nov 03, 2007 1:17 pm

Progress report,
From the last job. I have since taken it for a test run and it runs like a new bike, up to now. I am now running it on the correct fuel, oil and mix and a good gearbox oil ( Castrol sports edge 5w 30 from another post ) and all seems well. I think that Betas' just have a distictive engine noise that i will have to get used to. Once again thanks to David, Neo for the oil advice and also David Ryan from Beta sport who let me pick his brains for advice. It's a good thing this forum is here as I was able to read quite a few other posts about similar issues. I will give it a good run next week so all is well.
Cheers all
Davo