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Rev3 Engine Rebuild


zoomered
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Hi, I have been told that my 06 rev3 250 need an engine rebuild as noise from the main bearings,

 

How hard a job is this? Are there any guides out there?

 

Would i be better removing the engine and sending it to a company to do and who?

 

Thanks 

 

 

 

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I couldn't find '06 service manual, but this should answer some questions....

http://www.betausa.com/sites/default/files/pdf/2012Support/Service%20Manuals/Mototrial/2009-2012%20Evo%202%20stroke%20Engine.pdf

2006 Owners Manual:

http://www.betausa.com/sites/default/files/pdf/2006%20Rev%20Owners%20manual.pdf

2006 Parts:

http://www.betausa.com/sites/default/files/pdf/2012Support/Parts%20Diagrams/Mototrial/Full%20Size/2006%20Rev%20125-270%202%20stroke.pdf

I would start by confirming that it needs main bearings. I had a 2002 that I beat the snot out of, and never replaced main bearings.

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Main bearings are relatively common in a bike of that age. We did our 2002 rev a while back, it was 100% reliable but rattled like hell. Confirmed by removing the flywheel casing and you could feel the play in the crank. Fairly simple job for a competent mechanic, having the right tools for the job is a must, and if you've got the new bearings and crank seals you'd have it done in a weekend. I found a link via Google which described the job in detail with pics.

Edited by adamspad5
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To get at the main bearings you need to split the cases, this can be tricky without the right tools.

 

First off, get everything you need before hand, new bearings (make sure they are C3 rated mains), gaskets, seals, tools etc, it sounds silly but leaving an engine apart longer than needed and it's likely you'll forget where everything goes!

 

Some items are best removed while the engine is still in the bike, particularly the tight nuts of the clutch centre, flywheel and perhaps primary gear, otherwise you have trouble holding the engine still while applying enough torque to the nuts when it's on a bench.

 

Store the bits you remove together, like all the clutch items in one container and so on.

 

A few sheets of cardboard with a rough online of the engine (and which side it is) drawn on will help store the casing bolts, just push them through in the correct postions they came out.

 

A tool like this will hold the clutch centre to undo the nut.

It can also be used to hold the flywheel and primary gear too, so it's a bargain!

http://www.demon-tweeks.co.uk/Product.do?method=view&n=678&p=547524&c=215&utm_source=Google&utm_medium=Base&utm_campaign=Hand%20Tools&gclid=CL2N8sDWmMUCFSMUwwodpa4AqA

 

 

The correct flywheel puller is needed.

http://www.splatshop.co.uk/sherco-flywheel-puller.html?utm_source=google&utm_medium=shopping&utm_campaign=shopping&gclid=CMHLy-7XmMUCFernwgodd2oAow

 

 

Once you're down and ready to split the cases many will use a case splitter if they have one, but with a bit of care you can tap and wiggle them apart, but be gentle and take your time.

You'll ruin the case faces (and sealing will become an issue) levering them apart, so don't do it!

 

You need to heat around the cases/bearing to remove and install them.

Once the cases around the main bearings are hot enough (and expanded) the bearings should "tap" out.

If you find you are tempted to "bash" them out, they ain't hot enough!

Plenty of posts on youtube for that though.

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I use a few old clutch plates and hold them together with locking pliers to hold the clutch basket. If your ambitious, I suppose you could rivet them together. That's a lot cheaper than the special tool. And a penny in the primary drive gear will stop it from turning. Make sure it is an old copper penny and not the new steel/copper coated. The steel will damage the gear. I've never had a problem with copper.

Goudrons is right, you definitely want to do this in the frame, much easier.

I had a 96 Gas Gas that I beat the crap out of. After 9 years of abuse, it sounded like an antique sewing machine on FullTilt! So, one winter, I lugged it into my apartment, (don't tell my landlord!) and I overhauled it. The big end of the con-rod was extremely sloppy. See picture; it's hard to believe it ran OK and didn't grenade itself when I red-lined it! I replaced the rod, bearings and pins, and went up TWO sizes on the piston and rings (with NO changes to the cylinder) and it ran like new. Just be sure you replace what it needs and don't overlook anything.

 

 

post-21248-0-11880900-1430261286_thumb.jpgpost-21248-0-70155300-1430261321_thumb.jpgpost-21248-0-30284800-1430261358_thumb.jpg

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A Penny! Think I'm made of money?

Nice idea though.

 

I like the clutch holding as well.

A lot of people weld an arm to an old metal clutch plate to hold them, but one of those tools I linked to have quite a few uses, apart from clutches, flywheels, primary gears, it'll hold gearbox sprockets on bikes that require a nut to hold them on, Like my MAR.

I've also gripped a few crank pulleys on cars with them.

Edited by goudrons
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  • 3 weeks later...

Excellent help thanks. Really wish I had listened the clutch basket before I removed the engine. Circling behind the nut is kinda in the way of the nut. Is this normal? Do I need to mark any of these or do they all just go back on one way?

Kind regards

Thanks

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Excellent help thanks. Really wish I had listened the clutch basket before I removed the engine. Circling behind the nut is kinda in the way of the nut. Is this normal? Do I need to mark any of these or do they all just go back on one way?

Kind regards

Thanks

Does it look like my Gas Gas in the above picture? If you're talking about the metal flat washer that holds the nut on, just beat it flat with a cold chisel. It should be replaced, but I have re-used them. Some clutch baskets have alignment marks on the flanges, look them over carefully, usually, they'll go on in any position. If you look at the picture closely, you can see one of the towers for the clutch springs has a line stamped across where the bolt goes in. There is a similar mark on the clutch cover and they need to be put together so the lines match. I don't know if Beta has the same marks, just look it over and check the service manual.

Edited by fulltilt
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Does it look like my Gas Gas in the above picture? If you're talking about the metal flat washer that holds the nut on, just beat it flat with a cold chisel. It should be replaced, but I have re-used them. Some clutch baskets have alignment marks on the flanges, look them over carefully, usually, they'll go on in any position. If you look at the picture closely, you can see one of the towers for the clutch springs has a line stamped across where the bolt goes in. There is a similar mark on the clutch cover and they need to be put together so the lines match. I don't know if Beta has the same marks, just look it over and check the service manual.

post-21248-0-94834800-1431642030_thumb.jpgpost-21248-0-10067800-1431642041_thumb.jpg

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  • 2 years later...
 
 

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