Hi all a friend of mine has a 2007 Sherco 250 he was out at the weekend and the bike locked up on him anyway I’ve removed the engine and stripped it down the fault is the crank bearings one side has fell apart and the piston and barrel is scored so what I’m after is any info on companies that can resleeve or plate the barrel or even somewhere I could get a new or used barrel 

many thanks Chris 

Seals and bearings from any good reputable supplier look on Google that’s the Simple answer, there’s a clue to a good one?A repair to the barrel will depend upon costs for labour and materials plus parts. Piston and rings etc again Google for more info. Some members on this forum may have been in your position and may offer more useful info. An oversize to 270 cc might be possible but again costs may out weigh the value of a 2007 bike and the cost of repairs. Have you found the reason for the seizure? Hope you get sorted. Don’t forget there are many good dealers that can offer advice, parts and technical help.

Hi matey yes I’m pretty certain it was lack of 2 stroke and we have ordered a bottom end gasket set and seals and crank bearings the crank is good conrod good just the top end to deal with and i has a quick look earlier in work at the 290 piston can’t remember exact sizes but everything apart from bore size was the same I have access to all machinery to bore the barrel out etc just wondering if anyone has gone over size to that extent and if it worked ok. Looking at the thickness off the barrel wall I think I will get away with it  as for the costs etc I’ll be doing all the work myself so shouldn’t be too bad just a idea if someone has done it and if the barrel coped ok 

Langcourts are the go to guys in the uk for re nikosealing mx barrels at least

Edited January 4, 20188 yr by faussy

I’ve emailed them in hope they can help cheers matey

Langcourts all the way for sure mate, Ill second that. 

Whilst the crank is out,take it to a engineer to check that is still true after the lock up and the of it. They wont charge you much to make it true if its out.I rebuilt my full motor a few months back and had the crank trued as it was well out,runs like a dream now! 

Splatshop for Viton crank seals and factory sealed bearings. He may have an exchange cylinder already done.  if you send it to langcourts you will neeed to send a new piston with it for match-up as these things need to be +-.005 mm for the most part.