Yamaha SR125 problems.....

[CEDR]

So a while ago, I was having issues with my bike, which are *possibly* related to running a bit low on oil and an O-ring in the engine getting stuck. Seems to be free'd and fine now.

Next problem (yay!). On Sunday, it didn't want to start.

(It's a 1998 Yamaha SR125, 1998.)

Sometimes when I press the starter, it doesn't do anything, but I didn't think much of it. It usually starts pretty much first thing, no real problems. Choke out for about 60 seconds (any longer and the mix seems to get too rich and the bike starts to stutter), choke in, ready to go. Every now and then it backfires when I'm easing off the throttle, but no biggy.

Eventually managed to jump start it today, but the ignition was making a weird buzzy noise but not firing (I hope I'm using correct terminology!!). Rode to Oxford (30 miles) without a problem. On the way back it started fine, stopped to get petrol a few miles down the road, then it didn't want to start again (nothing when I pressed the ignition button). If I rolled it forwards gently, it then started fine!

Twice on the journey back it stalled and refused to restart unless I pushed it forwards and mini-jump-started it. When we got about 15 miles from home, I noticed an eggy smell. I've since looked that up and seen that it's most likely a battery problem (annoying as it's got a new battery) (link here to similar issue on a Honda: https://www.motorcycle.com/forum/honda/18703-rotten-eggs.html). My husband then also noticed that my high beam filament had blown (only a problem as I was relying on it as the normal headlight beam on the double filament bulb recently blew!). Luckily it wasn't dark!

Managed to limp it home carefully. From about that point onwards (half way home) I also noticed that as soon as I eased off on the throttle (in any gear) it started to almost backfire... not one loud bang, but a continuous back-firing kind of sound until I either stopped or eased the throttle back on. Nice!

So now I've got a bike with:
-possibly a battery problem (overcharging?)
-constant backfiring sound when I slow
-no front headlight (but we can't take it apart til we can find a replacement as the fittings are all rusted up and likely to fall appart, and we can't find a replacement)
-possible starter motor issue? (or is it just the battery problem?)

I have a Haynes manual, a willingness (but no knowledge) to get grubby and not so much money!


I will add that some f*cker broke into our garage and tried to hotwire my bike mid August, and despite the AA man kindly fixing my wiring the best he could, the headlight blew, the dashboard light blew (who needs to see the speedo in the dark anyway?!) and the neutral indicator light blew!


What would you recommend? If the best option is "take it to a motorbike garage, tell them the above, get a new credit card and pray", then fine... I'll do it!

Cheers all!

(I love my bike and just want to be back on the road!!)

[Robby]

Overcharging and blowing bulbs points at a reg/rec failure. The voltage is no longer being rectified, so the bike is running at 30-60v instead of 12v.

With the bike running, get a multimeter set to volts across the battery terminal and hold the revs at around 4000rpm. If you're seeing more than 16v, then you have a reg/rec problem. They aren't a notorious problem on that bike, so a second hand one should be a safe bet.

[CEDR]

[CEDR]

Any other helpful suggestions from anyone?

We're going to start working on it on Saturday... so wish us luck!

[CEDR]

Reg/rec replaced and new battery..... but bike still not starting

When you press the ignition there's nothing at all.