Beta 4T Normal or Noisy?

[thall1]

hi thanks for that... it now sounds similar to my sons, I might take out the tensioner and have a look.... I did try to reset it but it didn't move...

 

 

[section swept]

Your engine may just be one of those where the production tolerances have collided. Like all manufacturers they have production tolerances, otherwise you’d be into ‘blue printing’ this is where all measurements are exactly as on the designers blue print drawing/computer. So some engines have parts that are very close to the specifications and are known as ‘rogue engines’ very often producing slightly more than specified power eg an increase of as an example 3-4+ bhp. Whereas another engine might unfortunately end up being built from parts that are on the edge of specification positive and some parts on the negative side of acceptable, these would be your normal production engines. Then of course it is entirely feasible for an engine to be assembled where the mass of parts are all on the limit of acceptable and you end up with either a tight engine or a loose engine. That’s why no two bikes are the same, identical to look at, identical in the way they work....but wholely different in their sound when idling. One of the differences between a works bike and a standard one is that all of the transmission, gears, clutch, shafts etc will be measured, polished to remove stress lines that may turn into cracks etc. The engine will have been dimensioned so that it is as close to if not exactly as the blue print specifications.....a nice smooth, quietish engine producing nigh on max power..!

After reading what you have done to the bikes engine, listened to your video I have to say ( bearing in mind I’m not next to the actual bike) the engine sounds really good, not too noisy or rattling...in other words fine. I’ve heard thousands of engines and as many other experienced people may agree it’s not too difficult to recognise a running engine that has a fault or faults? You need to remember that the transmission is being driven while the engine is running so other components will be adding to the overall sound. 

Be aware that overloading the cam chain tensioner puts extra stress and strain on the tension guides, the tensioner it’s self and the drive sprockets, then there is the cam bearing and the crank bearings that will all be loaded if you overdo the tensioner loading. I would reset  the tensioner exactly as The manual stipulates. Then get on and ride the thing. 

Your very first video.....that’s valve clearances opened up, probably not set at pdi or after initial break in period. After setting those clearances, paranoia has set in and you can tune in to more noises, bit like a new car, nice and quiet for the first few days then the creaks and rattles develop......? 

Last video, sounds like the majority of four stroke engines....wouldn’t put me off buying it if it were on offer to me?

[mcman56]

Thanks for the input.  I have heard that dealers do not like to sell identical bikes to two friends because one will always be slower than the other and they get complaints.

I did not mean to imply that I put a lot of pressure on the tensioner.  The only thing I did different was rotate the engine.  The manual does not include a rotation.  Assuming there are tight and loose places on the chain like a rear wheel chain, static adjustment would be random.  With rotation it may adjust at the loosest point.      

 

[nzralphy]

Hi Sorry I'm late to the conversation. My 2008 Rev4T sounds like the second bike, I'd be happy to have the second video as my bike.

Edited December 30, 2018 by nzralphy