O'Neill Bro 29cc.... Yay or Nay?????

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ininja

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i jus been offered a O'neil bros 29cc engine brand new complete with clutch/carb/airfilter!!!
does anyone know anything about this engine and any known issues installing this on a baja 5b ss??

or should i jus recon my stock 26???
 
Whats the price? Free then go for it! Its not one that many will go out and purchase if there is a choice. Its the most known head kit to have plating issues which turn out to seize motors. Unsure if things have changed lately but there are others I would go with. Some get many years from one until the plating thins. Any reason you don't buy a new head kit for your 26 and rebuild it with new bearings, seals and gaskets? Would give you a new motor with a better choice and more knowledge in the rebuild.
 
Bigger the Better said:
Whats the price? Free then go for it! Its not one that many will go out and purchase if there is a choice. Its the most known head kit to have plating issues which turn out to seize motors. Unsure if things have changed lately but there are others I would go with. Some get many years from one until the plating thins. Any reason you don't buy a new head kit for your 26 and rebuild it with new bearings, seals and gaskets? Would give you a new motor with a better choice and more knowledge in the rebuild.
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i was thinking of jus rebuilding this stock 26 but i wanted to take my time..upgrading the engine over time but tht involves downtime!!!!
the o'neill engine is 200 !!!!
 
if your going to pay $200 for a used motor why not pay the extra $59 and get the new zenoa g270 4 bolt. 3.5 horses out of her.
 
I your going to go high power then pay and get new, tuned ported engines need new rings every 6 to 10 tanks and with used engines in general you never know how they have been treated unless of course you know the person selling the engine. There are guys I run with that buy cheap and replace often but what's the point?

You must be running hard to have blown the 26 in that car. learn to work on your car by buying a head kit and see where it gets you. The cy 26 is a well proven strong engine with only one real weakness (2 bolt).
 
yep you never know what you get. a buddy of mine bought a "30.5 esp modified" motor from some guy he didn't know. he doesn't know much about gas motors cause he's an electric guy. come to find out the motor was only a 23cc, cy block, zen head and he etched esp in the side. not to mention the motor was shot anyhow.
 
plus 1 on this mate i paid £100+ for a tuned 26cc zenoah it turned out to be crap well worn needed a top end kit i just robbed it for bits in the end but i got my 23cc oddified from ebay and thats a1 loads of life left so its all about luck
 
i did actually say it was brand new never started :w00t:!!!
i think im jus gonna recon this 26!!! bigga i haven't blown the engine but there is leaks around the head.

anybody got a chassis for sale???? :lol::lol:
 
I got a good power, just been rebuilt early adition MMR engine. 26cc cy is it, ported by scotty. Just had gaskets changed then been put in a box. I run a better motor so this one wont be used. Will sell for right price.
 
battyjason said:
I got a good power, just been rebuilt early adition MMR engine. 26cc cy is it, ported by scotty. Just had gaskets changed then been put in a box. I run a better motor so this one wont be used. Will sell for right price.
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whats the right price??? im in salford too :lol:
 
is it 2 bolt or 4 bolt and whether its cy or zenoah? if its ported by OBR and its brand new i would say go ahead for the price. 29cc with more torque is a + unless you looking for rpm.
 
ininja said:
i did actually say it was brand new never started :w00t:!!!
i think im jus gonna recon this 26!!! bigga i haven't blown the engine but there is leaks around the head.

anybody got a chassis for sale???? :lol::lol:
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Fair play ininja, but unless you know the guy selling the engine proceed with caution, what is described and what you get can and very often happen to be different. There are a lot of cow boys selling on Ebay, the various forums are full of members giving others the heads up on dodgy dealers.

CY 26 do blow head gaskets, mine blew three!! nothing wrong with this and it does not always mean the engine is toast, buy a copper head gasket (for strength) and rebuild. Make sure you set the squish properly set though as copper head gaskets tend to be thicker than the paper gaskets generally fitted to these engines. your squish needs to be no less than 0.4mm (any smaller and you can have piston smacking head problems) and no bigger than say 0.6 - 0.65 otherwise you start to lose power.

Watch a Daves Motors tutorial re setting this up.
 
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