Scott8155

No it doesn't blackhat, the noise kicks in at around 15mph, at first it was 25mph, and stops again when the bike slows down past 15mph

Sorry chaps I've been a busy bee. There's no stiff links in the chain, I know by only saying knocking you can't imagine my problem clearly but the noise is certainly coming from the bottom end of the engine, not the front sprocket/chain. I can't really feel it at the foot pegs but it's more of a loud slap and I don't think the vibrations would be strong enough to feel if that makes sense.

No it isn't blackhat, only when moving

Yeah I thought of that airhead, thanks though. I do keep on top of my chain maintenance. It definitely is coming from the bottom end and is a really loud knock

Pretty sure it's speed drewpy but I will double check

Alright chaps. So riding home from work my xt 125 2010 suddenly starts a loud knocking coming from the bottom end of the engine. It happens when the bike is moving past 15 mph, not when idling. Ideas ? I'm not a mechanic but I'm eager to split the engine and have a look and I've learnt slowly but surely. Would it be cheaper to buy a new bottom end or the parts depending on what it is?

Sorry I haven't replied in a while chaps. I've been so busy, family problems + uni and now the bike has gone bang all together!

You're on the ball there Blackheath, as I let go of the button there is usually a few small/weaker sparks. Tried that too airhead, no luck there either. It has both kevtherev, however the clutch one isn't activated now as my current lever is slightly different in shape, but the problem was found before I changed that. The side stand switch still does its job but I suppose could be defective still. Sorry for slow replies guys, been a very busy bee recently. Any idea on how to check the switches that cynic suggested?

Dickwad thanks for the suggestion but I think as cynic said the coil maybe ok as the engine does run, it's the electric start somewhere giving off one spark. How do I check these switches Cynic?

Tried that airhead and nothing. I've had the battery charger fully, and tested with a multimeter when done too.

Evening guys. So my problem is that when I use the electric start on my bike I get one or two sparks no matter how long I told the button then a slight spark when I depress the button. Sometimes this is enough to start my bike, however it WONT when the side stand is down. I usually use the kick start anyway. Its not the CDI as I have a new spare one. So are we thinking stator, ignition coil? Possibly the electric start button? My bike is a yamaha xt 125 2010 Thanks guys

Well the problem turned out to be a faulty wire from the starter relay, finally sorted it! Anyone have any ideas which wires on a yamaha will be the oil light and the EOBD light?

Give me a few hours dt, I'm at university at the moment, I will be home at 2ish, what time that is for you I don't know. Also, I have undone everything I did and wired my old speedo back in for now. One thing I forgot to add what someone has been in there before me (previous owner) and the wiring is shocking! After market indicators taped together, and some terrible crimps around the wiring loom. I'm no expert but Christ its awful. Quick thought; is it within forum rules for me to post the diagram? Well unless I'm missing something, its not the cdi unit, new part just came and I plugged it in. God sake

I'll put one up when I get chance tomorrow, my manual is in the garage. I may be wrong, he's the expert not me aha. I have seen the headlight relay and it attaches just above the cdi. Well regardless of if this is correct or not, we will see when the new part comes this week. Hopefully he was right

My dad's friend is an electrical whiz and showed me why he thought that was so. The headlight relay is behind the cdi so the circuit breaks before its getting there. So we'll see when the new part comes in a few days. I'll let you know dt.

Hi guys. So after a bit of tinkering and testing it's come down to potentially being the cdi unit. Bad times

I was fiddling with the fuse holder so you may be right. Good news is my dad and his friend are gonna have a look whilst I'm at work over the weekend, they're do better than me at it!

Just a quick idea guys. So a wire from the ecu mounts onto either the positive or negative part of the ignition coil. I'm not saying I have, but if I've put this together the wrong way, e.g. put this wire onto the negative when it may have to go on the positive, then may this be my problem?

Thanks for that Slice, I only ask about a yamy dealer doing it so I know that's there as a last resort. Sad thing is I was gonna sell up for something better when I got this done the other day aha, ah well at least I'll learn something new by getting this sorted. If putting the old speedometer on doesn't make the bike run then I'll just go nuts on the wiring with a multimeter ahah. I'll post up any findings, if any!

Thanks dt. I'll check the ignition next. Unfortunately it's not the kill switch, even though I wish it was. The battery is fully charged as that has been checked already. All I did was cut my speedometer out and start fitting the new one, at first I just connected the power wire from the battery and the power for the ignition, grounded it also, then tested the bike and the Speedo worked and the bike started also. Then I connected the rest of the speedo, which during this the only wire on the bike I messed with away from the speedo was once attached to the ignition coil, which was so I could fit a wire provided to get the rpm reading. I of course reconnected this wire when trying to start the bike. My dad is going to have a look tomorrow, as well as his friend who is good with electrics, so hopefully they'll find the problem. Would yamaha still look at my bike if I wanted this aftermarket speedo fitted?

I'll do that. It will be tomorrow now. The only wires I have intentionally touched are the ones coming out of my speedometer and I cut them close to the pin connector. But I'm open to any suggestions aha. I've only been on my bike a few months and this is the first electrical 'experience' I've had. So its probably something stupid I've done

Yeah the battery was new 2 months ago and it was working perfectly just before I stripped the bike. I couldn't start the bike by kicking it either so even a battery with low energy can't be the case

Not a thing, Airhead. Tried everything electrical on the bike just to check. Not a thing

The fuse I replaced wasn't even blown! So Thats me out of ideas already :/

Hey guys. So I'm fitting a new speedometer to my yamaha xt 125 x 2010, a koso dbo1r I think it's called. Any way, I stripped the bikes panels off, took out the old speedometer and began wiring my new one in. When I had wired the power cables I tested the Speedo/bike by connecting the battery back up and watching the speedo light up as it should. At that point I started my bike too just to check if it would. After that I began wiring the rest of the speedo, this including a 'rpm wire' which connected to the ignition coil. I then tested the bike again to find nothing. No electrics and therefore the bike wouldn't start either. I checked the ground and changed the fuse. Nothing. Any ideas? I'm no electrician or mechanic so sorry in advance if I missed anything or said something incorrect.