Suspect Crankseal

Hey guys well i've had a shocker today racing Endurocross, Sighting lap was fine, 4th out the gate, no probs here, about half a lap in my bike started to bog intermittently and at one point died altogether, managed to get it back going anyhows but was not right. A few corners later i came over a brow probably a little faster than i should as i was heading to the pits and some clown had fallen off his bike and blocked the track completely resulting in me slamming into his fallen steed and sending me over the bars trashing me helmet :confused:. Finally limped to the pits and noticed my carb overflowing which i thought was the problem, stripped and cleaned it, still overflowing and running problem persisting, stripped it again, carb fine problem still there, would rev fine then bog or not rev out fully. Put a new plug in and fired it up still a problem, fired it up again hoping the problem would somehow of fixed itself :thumbsup: which resulted in a kickback from the kickstart and a loud pop which somehow managed to pop the rubber grommet the stator cable runs though out of the engine casing, My question is was this seal the original culpret to its bogging/running issues or has my messing around blown the crankseal on the ignition side? any help appreciated as i know there could be a number of faults for this mishap!

Well i've ordered a couple of crankseals, removed the ignition side and will replace that as i know i've had a leak though there, plugs been replaced and the stator is no more than 6 months old, carbs clean. Is there anything else you guys can suggest?

Compression good? Reeds sealing up? Pull the pipe and take a peak up the exhaust port at the piston....

Compression good? Reeds sealing up? Pull the pipe and take a peak up the exhaust port at the piston....

Yeah the reeds did look visually good, im going to strip and clean the carb again so i will have a better look then, compression seems to be good although i do have a piston on the shelf ready to go in! Will pull the pipe and have a look in a moment!

Did you check the pilot jet?

I would say either reeds are damaged or new rings are required.

I find as soon as the rings get past there useful life it starts getting just that bit harder to start and easier to stall.

Right i spent a few hours working on the bike tonight, Replaced the ignition side Crankseal, Cleaned the carb, replaced the reeds with some new oem ones. I had a new (aftermarket) stator within the last 6 months and i wondered if this could be suspect, before i installed it i checked the resistance of the coils and all were in tolerance with the manual, However i noticed tonight the source coil is reading 630 ohms whereas the manual specifies 720-1080 ohms, could this be the problem with the bike? It starts fine and i can see no blowby on the rings which leads me to think the compressions ok. When running the bike will not seem to rev out and the revs fluctuate up and down when the throttles wot or it will bog and die completely but start fine afterwards, it hard to explain what im hearing to be honest, What do you guys think?

Are you losing and coolant?

Do you still have the stock stator? If so, I would pop that back in and see if the problem goes away.

Why did you replace the stock stator? They normally don't go bad and unless you are running lights, then the stock one is going to be the best bet. Your reading being more than 10% lower than what the stator manufacturer states (did you check it as per the stator manufacturer or OEM test specs?) as acceptable could be either the meter not reading correctly, or a weak (faulty) stator.

The thing with manuals stating what the ohm measurements should be is that they (the manufacurers) use calibrated tools to test and measure voltages and resistance. Your meter could be giving false readings (especially if the battery(ies) are weak) or if it is old, cheap or has been abused.

Replace your ohmmeter batts and retest, and if you get the same results, see if someone you know has a meter you can borrow.

Or, just put the stock stator back in and see if everything is good to go.

Haven't noticed any coolant drop, haven't touched it for months and when I drained it last night it was still full to the cap, the stock stator is toast and it won't even start with that. I've emailed the manufacturers to see what they say. Not really sure where to go with this now!

I had a new (aftermarket) stator within the last 6 months and i wondered if this could be suspect, before i installed it i checked the resistance of the coils and all were in tolerance with the manual, However i noticed tonight the source coil is reading 630 ohms whereas the manual specifies 720-1080 ohms, could this be the problem with the bike? ?

This is were I would be looking

This is were I would be looking

This is it im sure, i noticed that it stank when i took the ignition cover off the bike and when i fired it up i noticed a small amount of smoke from that region, i assumed it was coming from the crankseal hence why i replaced it!, i whipped the stator off at lunchtime and had a closer inspection and noticed on one of the coils has a scorch mark on it, i reckon its breaking up under load, im posting it back to them tomorrow so they can test it properly and hopefully send me a new one! bloody things only 4 months old! I should have had the Oem one rewound in the first place!:smirk:

I would personally just get another OEM stator. They are extremely durable and yours is the first one that I have heard of failing in a very long time.

Are you running lights or heated grips or something that requires an aftermarket stator?

I would personally just get another OEM stator. They are extremely durable and yours is the first one that I have heard of failing in a very long time.

Are you running lights or heated grips or something that requires an aftermarket stator?

At the time i was quoted an 8 week wait for a new oem one i believe and it was ridiculously expensive! I may see if theres a good used part about, in the meantime im sending this one back for either a refund or replacement!

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