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I am hoping someone will be able to help me out with the charging system on my bike. I purchased the bike and rode it home. Later in the night we went to turn it on again and it struggled to crank over. We then push started it but it died when the bike came to a stand still. Purchased a new battery and a new reg/rec and even with the brand new fully charged yuasa battery the bike died on me while at a roundabout, and being fresh out of stay upright that was a bit of a stressful moment sitting there blocking up traffic trying to start the bike with a dying battery. My friend and mechanic uncle who had some bikes flat out said I should just cut my losses and sell it and get a better one or take it into a mechanic to get it fixed. Id love to just take it to a mechanic and get it fixed however funds is low and I'd rather just fix the bike myself as I got it for a fairly low price. I inquired about just taking it in for diagnosis but Id have to wait for over a week and itll cost a fair bit also. I dont want to sell it as I love it already even though I've hardly ridden it and I doubt I will be able to find another one for the price I got it for as I checked out other mc22s of similar price however the one I chose was the one that rode and looked the best. My friend who helped with the process also said the bike rode like a machine.

I purchased a multimeter and followed what videos and threads I could find. Being the first time using a multimeter in real life out of highschool, I largely depended on step by step guides however most videos weren't mc22 specific so it took a bit of head banging to get my head around certain things/concepts. The voltage that the reg/rec gives/(or takes) from the battery is around 12.5-12.6v which is fine. The old reg/rec only reached about 11-11.5v, so the new reg/rec did help. We did some testing to the stator such as resistance and AC and whatnot and the resistance was fine, about 0.5-1. The AC voltage from the stator was only 30-35v which is bad as it should be about 50-60v apparently according to friend.

The voltage of the battery when turned on is about 12-12.5 but when revving to about 4k+ (even went hard and reached 15k one time) the battery voltage would be about 11.8-12.3v, which is bad, as it should be 13+v so the battery can charge up. Being convinced the stator is at fault, we did further testing between different plugs and components and my friend (who is more experienced than me in bikes and is a pretty decent electrician as he helps his father out) said its probably the stator and we should sus it out.

Being so certain it was the stator, I ordered a 2nd hand one online and waited until it arrived to open the bike up as we didn't have much time in between to even check out the current stator. Today however we opened everything up only to find out the fucking current stator is in perfect if not better condition than the $100 2nd hand one I had ready to replace. Its not all that bad as I can just resell the part and patiently wait until I find out what is actually wrong with the bike, thing is, we aren't too sure what to do next. My friend is feeling confident that when he comes around next time in a few days that he will be able to sort something out, like maybe finding a burnt connector or something, but he asked me to post on this forum to see if anyone can will be able to provide clear and precise suggestions on how to go about finding a solution.

I also purchased a new reg/rec plug (the 5 pin connector with the green, red and 3 yellow cables) and will replace the one on the bike to see if that helps with anything.

Thanks for reading the long winded post and hopefully I gave as much useful info as I could. I apologies for not including all the numbers I got for the different tests I did with the multimeter but I honestly can't remember them all, except for the resistance of the stator plug near the battery. If you require me to perform certain tests, please tell me exactly how to go about doing it and I'll tell you what the results are.

Will shout a deck, a stick or whatever to anyone who finds the solution or greatly aided us in finding the problem.


62 Posts
Not sure if you have sorted this or not yet.

This a simple yet fault yet so often over looked and missed diagnosed.

On the rear brake side of battery is your starter relay. It has a red plug on top.

You need to squeeze to locking tabs either side a wriggle it off.

Underneath you'll find main 30amp fuse and 4 male spade terminals and 4 female spade terminals in plug.

All power to bike and battery must travel between these terminals.

Most of these are corroded and will cause exactly what your bike is doing.

Loads up battery and regulator also.

Causes disco lights at idle when blinkers are on in dash.

Check for corrison on fuse blades also..
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