Why doesn't my DT125 get a spark?

claws

A bit of a long story for a simple ending but yea.

So a few days back I was messing with the YPVS and getting it setup since it was making the bike really slow as the valve was pretty much closed. So I got it sorted out but it wasnt completely in tune so I tuned it more and got it all good and did a few wheelies until my idle revs started rising very much.
At that point I thought that my throttle cable got stuck or something and sorted that out as well. Didn't help anything. After that I took the carburetor out, cleaned the jets and tuned the fuel level just a bit. Then I put everything together and tried to start it and nothing. Then I thought that the spark plug must have gotten wet or something.
I took the plug out and dried it up. After that I tested if it gets a spark with the plug out of the head and when I turned the main switch on I got an electric shock which startled me a bit. But when i tried to kick start the bike to see if it got a spark, nothing. Nothing at all. I tried another spark plug and nothing.

So what could be the issue? I think it could be either the stator or the cdi. Not sure yet.

Calum

Common issues on these bikes tend to be, side stand switch, neutral switch and kill switch. Make sure those are good.

Check the ignition barrel connector block, you may have disturbed it when faffing about.

Easiest way to sort the power valve out is to take the exhaust off and line the valve up with the port directly.

oldman

Change the spark plug anyway. Low cost item and can then be ruled our completely

claws

@Calum I could open up the kill switch and see if that is working correctly. I doubt that the main switch or the side stand switch have something wrong with them since the rear light turns on when I flip the power on and I don't have a side stand switch actually

claws

@oldman yea I think I could switch a new plug in when I fix the bike. Just a bit shitty that the iridium plug stopped working after like one month

NINJA

@claws Iridium plugs tend to have a shorter lifespan over regular plugs. Mainly due to the stronger spark they produce. I used Iridium plugs in my DTR and noticed a definite drop in performance after a month's use. As plugs are as cheap_as_chips they are an easy component to replace.

claws

@NINJA kinda disappointing to spend 15 euros for a plug that doesnt even work for a month though. will go with the ngk br9es plug from now on since its like 4 euros

NINJA

@claws The iridium plugs are cheaper on ebay, especially if you buy 4 at a time like I do; :winking_face: :grinning_face_with_smiling_eyes: :winking_face:

https://www.ebay.co.uk/itm/BR10EIX-NGK-Spark-Plug-Sparkplug-Type-Iridium-IX-NEW-No-6801/272479003527?hash=item3f7103a387:g:OWUAAOSwo4pYSYqN

Calum

I have had the same iridium for years. My starlet has had the same iridium for years too.

DTRLuke

Yes, not normal for any spark plug to be needing replacement within a month. It'd say something about how your engine is running. Too lean or too rich.

claws

@DTRLuke the stock carburetor was running pretty badly and i couldnt really tune it either since the screws were seized so i switched to a 36mm keihin pwk. it was running pretty good actually until i switched a few things including the fuel tank

DTRLuke

@claws
You can buy chinese remade DT carbs, a few people have them on their bikes. A lot probably don't even realise they have a fake carb.

declan

@DTRLuke yeah they’re only 50 pound look decent

NINJA

@declan £50 quid - BARGAIN!!!

claws

@DTRLuke actually paid around 50 pounds for the keihin carburetor

declan

@NINJA yeah it really isn’t a bad price

DTRLuke

@claws The Keihin carb is probably also fake. Most carb's are fake on eBay etc. If you order one directly from Yamaha, then it's most probably OEM, but will be double the price of the fake.

claws

@DTRLuke no no no i bought the carburetor as a used one that was taken from a ktm exc 125

declan

@claws still could be fake

claws

@declan well yea but since the carburetor works i dont really care