Hi Guys,

My youngest bro has bought himself a 1999 SR125 to run around on whilst at uni. When its warm it runs perfectly, no surging, no stalling, idles forever, hits 60-65mph etc.

It can be an absolute mare to start in the morning though. I changed the battery, spark plug, oil change and checked the valve clearances. It seemed to help a little but is struggling to start again without a jump or bump. I should mention that it starts pretty quickly with a jump from a car battery (with car engine off).

Hopefully he isnt just doing it wrong, I've explained the choke and that it needs to warm up etc to him, but it is his first bike.

He is going to leave it with me for a week so i can sort it out, and my priority list is as follows:

1. Replace air filter and strip and clean carb.

2. Carb rubber between carb and head looks split so need to try source another one (anyone any ideas where to find one? May have to go to a scrap yard and find any pipe that is similar size)

3. Starter motor issue, could be weak turnover but never had to check this kind of thing before so will be new to me. Brushes etc?

After this im not sure what could be causing it as it runs brilliantly when warm.

Cheers folks,

Dave

Oh, I checked the voltages over the battery when running and it holds 14.5volts nicely so charging system seems good

yeah sort the carb rubber first Dave, maybe it is just a surface split though and so not causing trouble, to prove just spray the split with WD40 or something with the engine running...see if it has any effect. Try Fowlers of Bristol for parts

Cheers for that, they have them in stock, but does anyone see any problem if I wraped the carb-to-head manifold rubber in duck tape or insulating tape as a temp fix?

petrol may dissolve the adhesive? I suppose it may last a short while if needs must

Old CX's have this issue with perished inlet rubbers and I've heard one can use a tight fitting length of old innertube as a virtually invisible repair. Me? No, that's bodging and I don't do that sort of thing, honest guv.....