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Hi, Im new to 2 strokes. I have a 2007 CR125 (bored to 150), It has been used mostly by its previous owner to race moter cross. However I am only in a position to ride it in the bush. I have ridden the bike 3 times, first 2 times with no problem, but today on the third ride I had plug problems.

I am a bit new to riding (previous bike was a 96 XR200), and dont ride it on the band at all times in the bush and am fouling plugs. I am only getting about 20 minutes from a plug and at $17.00 a pop its a bit expensive. When a new plug is installed, the bike starts first kick, no way will it start with an old plug (not even clutch starting)

Also today we were deep in the bush and ran out of plugs and had to push the bike out (hard work).

Questions are can I rejet for the bush, should I change my fuel mix. Can the old plugs be bought back to life ? They just seemed oiled up ! Surly CR125s are not just for motor cross tracks.

Plugs Im using are NGK ® BR8ES

Any help would be appreciated.

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Hi im new here , recently ( about a month ago ) i bought a ktm 125 sx 2000 model for £900 and have had to fix the exhaust , back wheel and changed the plug on it but yesterday my friend was out on it and it just died ... he said it just bogged out but the bike is getting very very low compression so im thinking the piston and or rings have went , YOU CAN ALSO KICK THE KICKSTART ALL THE WAY TO THE FOOT PEG THATS NOT RIGHT EH ? was just wondering if any1 could help me out , do you need to re-sleeve the barrel every time you change the piston ? please get back to me as soon as possible because im really gutted after just spending like a grand on it n it to be sitting like that thanks in advance.

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Hi, Im new to 2 strokes. I have a 2007 CR125 (bored to 150), It has been used mostly by its previous owner to race moter cross. However I am only in a position to ride it in the bush. I have ridden the bike 3 times, first 2 times with no problem, but today on the third ride I had plug problems.

I am a bit new to riding (previous bike was a 96 XR200), and dont ride it on the band at all times in the bush and am fouling plugs. I am only getting about 20 minutes from a plug and at $17.00 a pop its a bit expensive. When a new plug is installed, the bike starts first kick, no way will it start with an old plug (not even clutch starting)

Also today we were deep in the bush and ran out of plugs and had to push the bike out (hard work).

Questions are can I rejet for the bush, should I change my fuel mix. Can the old plugs be bought back to life ? They just seemed oiled up ! Surly CR125s are not just for motor cross tracks.

Plugs Im using are NGK ® BR8ES

Any help would be appreciated.

You stated bored to a 150cc..............Whats your Piston size? Do you know where your jetting is set at right now?

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Hi im new here , recently ( about a month ago ) i bought a ktm 125 sx 2000 model for £900 and have had to fix the exhaust , back wheel and changed the plug on it but yesterday my friend was out on it and it just died ... he said it just bogged out but the bike is getting very very low compression so im thinking the piston and or rings have went , YOU CAN ALSO KICK THE KICKSTART ALL THE WAY TO THE FOOT PEG THATS NOT RIGHT EH ? was just wondering if any1 could help me out , do you need to re-sleeve the barrel every time you change the piston ? please get back to me as soon as possible because im really gutted after just spending like a grand on it n it to be sitting like that thanks in advance.

Depends if the Nikasil plating of the cylinder bore is damaged at all. If damaged you can ether have it re plated or install a cast iron sleeve.

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so if its scratched at all i will need to send it away to get it replated ? or is there a borderline for the marks , im just taking the barrel off the now to see the damage

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My big brother's friend had the same problem on a cr 125, it would foul 3 plugs in 3 hours of riding. He rebuilt the top end and that stopped the problem. And as for the fouled plugs, just save them and clean them and they should work again.

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chek ur compression 1st, its easiest, if its decent (above 130)and at 130 thats low. maybe too low for it being bored, but im not sure bout that. then chek ur jetts/carb. but, ya its more than likely in need of a topend job. as for a damaged cyl. the reputible rplating companies can fix anything it'll just cost abit more. typically, 200 for replating, without damage, with, its about 75-100 more. Millenium technologies has an exchange program but it has guidelines for the cylinders they exchange for. all info is on their website. Geez, if u pay the shipping i'll send ya some plugs can get them for 5 buks.

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Throw them in some seafoam to bring'em back. Rejet for bush. 2 strokes need to be ridden hard.

My CR80 does NOT like trails when improperly jetted. When its jetted for racing it doesn't like the trails. 80's are meant to be screaming all the time. Same goes with your bike most likely.

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