OzVMX Forum
Clubroom => General Discussion => Topic started by: oldskool on May 02, 2010, 05:34:31 pm
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hi does anyone know if you can buy a bigger piston than 56mm and go bigger on the bore on a cr 125 rh? if not does anyone know the cost of a resleave? or a good barrel and head as the head on mine has some damage,looks like something has been ion top of the piston at some stage looks like pitting on the inside of the head,top of piston looks fine so must be from a previous rebuild.thanx cheers gary
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search for LA Sleeve - anywhere between $100 and $150 US plus installation, piston and rings.
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anytime I talk to anyone about a resleeve on a big bore the average figure of about $500 comes into the conversation. Sounds scary but this price includes the sleeve obviously, also the fitting and any machining/boring as well as the piston kit and all top end gaskets. When broken down it's not such a bad price..sort of.. :-\...maybe.. ??? that's the story I normally get anyway ;) the pitting in the head chamber would be from a prior rebuild if the piston dome is unscathed. The mark of detonation ;)
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thanx all i may just look for a second hand barrel.that was my thought doc piston seems fine on top it only has 1 ring on it the bike ran well even when the compression was low so the head may be fine i hope,bottom end feels good and just as the compression started getting low it started fouling plugsthe ring that is still on the piston seems to be stuck on there it wont even move around.i have a full engine gasket for it from bk performance.so anyone know of a barrel to suit 87 mod cr 125 i think there the same from 86 to 89.thanx again cheers gary
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Sleeves only , made to your spec $350
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there seems to be an abundance of sleeves both LA and Wiseco on eBay US Gary and all around $90-$125US..if you are thinking of resleeve then maybe this is worth a thought :)
http://cgi.ebay.com/ebaymotors/CR250-CR250r-Big-Bore-295cc-Cylinder-Sleeve-87-91-/130373481940?cmd=ViewItem&pt=Motorcycles_Parts_Accessories&hash=item1e5add75d4 (http://cgi.ebay.com/ebaymotors/CR250-CR250r-Big-Bore-295cc-Cylinder-Sleeve-87-91-/130373481940?cmd=ViewItem&pt=Motorcycles_Parts_Accessories&hash=item1e5add75d4)
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thanx doc one for my bike is about $130.14 aud delivered know anyone who fits these.cheers gary
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if you consider the big bore kit just be aware that the power valves will need to be modified (shortened) and there will be no turning back once you do this.
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thanx hooney but no big bore kit just standard size trying to do on a tight budget,or second hand barrel will be fine.thanx cheers gary
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Unforunately resleeves are not easy or cheap as plenty of early cast iron liners were cast in during the maunfacturing process. The liner is cheap because all the work in in getting to old one out and machining the cylinder to accept the new liner.
Beware the cheap cylinder as you have to be certain there is a few rebores left.
Alternatively you could just use the 84-85 piston which go up to 57 odd mm ;)
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taanx lozza but theres a bit of a mark in the bore and even at 57mm it might not machine out but its worth a try the bore is at 56mm now ill take it to a shop on wed and see what he reckons as this is all new to me.thanz again cheers gary
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Oldskool, where are you located?
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hoony im in se qld near yatala about 10 min from oldfarts area
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thanx everyone ive found a barrel in a wreckers in bris the bore is at 50mm so it has a couple of bores left in it $135,so i think ill go with that.thanx again all cheers gary
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hoony im in se qld near yatala about 10 min from oldfarts area
Pie Country ;)
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im only about 3 min drive from the pie shop ;D
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if the bore is scored on one face you can get the rebore man to offset the boring bar,ive done this to clean up a bore on a tt500 barrel with had a bad groves in the bore when the previous owner forgot to install one piston clip