THIS POST HAS BEEN UPDATED 05/2020
There have been main bearings failures on late model Xtrainer RR250 and RR300 models, some as low as one hour of riding. Beta USA indicates it is occurring in about 5% of cases.
WHICH YEAR MODELS ARE AFFECTED?
The problem began in 2018 models and continued into the 2019 range at which point Beta head office said they fixed the problem. Unfortunately it seems the problem is continuing with the 2020 models although the numbers suggest it's about half the rate so far according to a reliable source.
THE CAUSE OF MAIN BEARING FAILURES?
Owners suspected oil injection issues which turned out to not be true. Beta head office has given very few details the past two years. Eventually they said it was an 'assembly problem' in the factory. They later changed this to it being a 'supplier problem' with incorrect bearings supplied (for more info, see further down). A recent chat with a distributor indicates it is back to being an assembly problem.
WHAT SUPPORT CAN YOU EXPECT FROM BETA?
Beta head office has now publicly stated they will repair all main bearing failures in or out of warranty (with the obvious exception of user error e.g. drowned engines, running without oil etc).
Beta head office pays five hours labour for repairs, but not for fluids. There have been reports of dealers charging for fluids and possibly a portion of labour if it takes longer than five hours - most dealers are paying the difference out of their own pocket though.
However, the level of support may change after 90 hours (at least in Australia), as the Beta manual recommends replacing the main bearings at this point. This is widely regarded as being for race bikes only, but it does technically give Beta the option of not fixing the bike after this. In most international cases, Beta is still repairing bikes but in some cases they are only providing parts, and not paying for labor, or just a percentage. If you disagree with this, you may need to take your case to your Beta distributor, then Beta head office, then finally pursue your case through consumer law.
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MORE INFO ABOUT THE POSSIBLE CAUSE
There were lots of early theories mainly around the oil injection failing or a bad batch of bearings - there was no real evidence of either.
Given the lack of detail from the factory, there's a bit of an informal worldwide network formed over the past year trying to get to the bottom of it all. I just checked in to see if there was any more info available.
Their current opinion? It appears to be three likely causes.
One, the interference fit is very tight for the left hand main bearing. So warm the engine case in an oven (don't use a blow torch as this may warp the case), put the bearing in a freezer, then it should go in with almost no pressure. It's possible some bearings may have been damaged by being forced in, just heating the cases meant a lot of pressure can be needed to overcome the very tight interference fit.
Two. Once it's all together, check that the crank is spinning freely. If not, tap the case until lateral pressure is relieved on the bearing so the crank spins freely. It's possible that unrelieved lateral pressure may cause the bearing to wear prematurely.
Three, ensure the left hand engine case is heated evenly in an oven when installing the main bearing. It appears that Beta head office did eventually admit to at least one distributor that the 'assembly problem' was incorrect heating of the engine case which caused warping. I don't know if Beta mechanics would have a way to check this reliably or not. But where a second or third main bearing failure has occurred (despite correct installation as above) then a new engine case could be required.
BETA'S OFFICIAL RESPONSE - IT'S AN 'ASSEMBLY PROBLEM'
Initially Beta head office did not respond to our repeated inquiries about all these main bearing failures. But once the issue became a public one, the Beta USA distributor did contact head office and told us it as an 'assembly issue' but with no further details... and that head office agreed to fix all main bearing failures under warranty even if the bike was outside of the six month warranty. They also confirmed main bearing failures were occurring in about 5% of the two stroke models.
Beta head office then changed tack and said it was an error by the bearing supplier.
Beta head office further complicated the issue by coming out with a different reason some months later, saying it was an error by their supplier and that the wrong bearings were supplied... which seems to contradict their earlier statement and how did they manage to use the wrong bearings through 2018 and 2019 production (and now 2020 cases are emerging), despite all the reported failure.! You can read the details here.
While Beta head office has not publicly provided any details, we did hear through a distributor that the original 'assembly problem' was the left hand engine case wasn't being evenly heated in an oven... and the localized heating of the main bearing area was warping some cases. This could explain why some owners have had three main bearing failures in a row.
We can only hope head office has made all Beta dealers and mechanics aware of this. Sadly we have heard some dealers still haven't even been informed about this main bearing failure problem. Beta head office needs to start issuing service bulletins to their distributors and dealers, as all the other major manufacturers do.
SOME TYPICAL CASES
While not an exhaustive list, here are some typical cases (many compiled from Facebook here and here) showing it's across various models and years with a range of hours on the engine...
Beta Xtrainer 2020 main bearing failed at six hours, fixed under warranty
Beta RR250 2020 main bearing failed at 36 hours, fixed under warranty
Beta RR250 2020 main bearing failed at 47 hours, fixed under warranty
2020 Beta RR300 main bearing failed at 500km
Beta 300RR 2019 bearing failed at 9 hours, repaired though just outside warranty
Beta RR250 2019 main bearing failed twice, first at 30 hours, again at 60 hours, both fixed under warranty by Beta mechanic
Beta RR250 2020 main bearing failed at 36 hours, fixed under warranty
Beta RR250 2019 main bearing failed twice, first at 30 hours, again at 60 hours, both fixed under warranty
Beta Xtrainer 2018 main bearing failed at less than 1 hour Completely fixed under warranty. Mechanic suspects faulty bearings or incorrect installation at factory.
Beta Xtrainer 2019 Main bearing noise at 7 hours. Took back to the shop and mechanic confirmed bearing was faulty, replaced under warranty.
2019 RR300 Main bearing failure at 12 hours Almost no warning, just five seconds of squealing then complete failure.
Beta Xtrainer 2018 main bearing failed at 8 hours. The dealer claims it was water damage but the bike was only washed once and ridden nowhere near water, the owner thinks it must have been a poor quality bearing.
2019 RR300 Two main bearing failures 15 hours then 21 hours Left hand bearing seized, Beta supplied parts but not labour. Within one hour the new bearing was noisy. Dealer refused to fix it.
Beta Xtrainer 2018 Main bearing failed at 10 hours. Dealer said this is a known issue so fixed under warranty and extended warranty by six months too.
Beta Xtrainer 2018 main bearing failed at less than 20 hours. Emailed for details but none as yet.
2018 RR250 Main bearing failed at 20 hours Beta UK fixed and rebuilt under warranty.
RR300 2018 Two cases of main bearing failure. Oil pump failed first ride, dealer replaced. Next oil pump failed third ride, changed to premix. First main bearing failed at 30 hours. Fixed under warranty, main bearings failed again at 60 hours. Beta would not fix under warranty again so had to pay.
RR250 2018 30 hours main bearing failure and wrecked the bottom end, cases, piston and barrel. Fixed under warranty and advised there was no lubrication issue, just a faulty main bearing.
RR300 2018 failed at 36 hours. No apparent reason, bearings were very dry and had just started to disintegrate when he stopped. In the same forum post, another rider reported his 2016 RR300 but he hasn't responded to my request for details yet.
RR250 2018 failed at 18 hours. Emailed for details, no reply as yet.
2018 RR250 Main bearing failure at 40 hours Not under warranty so fixed at his own expense.
Beta Xtrainer 2018 Main bearing seized at 900km for no apparent reason. Out of warranty but dealer covered half the costs.
2017 RR300 & 2018 RR300s Both failed at around 60 hours Beta dealer fixed both under warranty, saying Beta recognizes the issue and the cause is either the bearings themselves, incorrect bearing, or incorrect assembly at factory.
2018 RR250 Failed at 60 hours, then 160 hours, then 212 hours. Eventually it was discovered the engine case was warped at the factory by being overheated when the left hand bearing was fitted.
RR300 2017 93 hours Stopped riding after bad vibrations started, suspected main bearing and splitting the cases now, he'll inform me if it is actually the main bearings.
RR300 2016 & 2015 Xtrainer 50 hours Main bearing failed. Evidence of surface rust on crank but no moisture evident. Owner has never swamped the bike and has no idea on how water would get in there. He also has a riding buddy whose 2015 Xtrainer had seized main bearings at 180 hours but no details as yet.
RR300 2015 84 hours owner stopped riding when a high pitched squeal started. Split cases and the lefthand main bearing was toast. Dealer provided free parts but owner did the work himself.
Xtrainer 2015 900km, unsure of hours. Out of warranty but dealer/distributor paid 50% of repairs as there was no apparent cause for main bearing failure.