Ricco1

Cheers yes it's definitely snapped off inside. I can remove the back 3 inches or so with pliers, I can see where the pipe has sheared off, and then the rest of the baffle stuck inside. I thought about trying to get the rest of it out but if a previous owner snapped it trying to do this, it's not going to be easy with little to get hold of. Plus, I'm struggling to find a listing for a new baffle so might be left without one at all. I guess I'm left with the option to give the caustic soda a go, or scour the world for a replacement exhaust and baffle.

The exhaust baffle on my Yamaha RS125 has snapped, presumably when I previous owner tried to remove it for cleaning. I'll need to decoke the exhaust at some stage, want to weigh up the options. Obviously a new exhaust would be useful but they are very rare, as is the baffle. Would filling the silencer pipe with caustic soda or the like, baffle in, do the job? Any other ideas? Cheers.

I'd first remove the fuel line from the carb, switch the petrol on, and make sure there's a good flow of fuel. Assuming that's OK I'd remove and dismantle the carb, check that the jets are clear, float is working correctly etc.. It might sound daunting but it's pretty simple. It's sometimes tricky to get the carb away from the manifold from the airbox but take your time, don't force it too much, you'll be fine. I've taken mine off 5 times now, dirty fuel problem, I can now take it off, dismantle, check, put back on, in 20 minutes. I'm certainly no expert.

Is an incorrectly set float height likely to cause the fuel starvation issue I'm facing, what else could it be? Struggling with this!

As far as I know the carb doesn't have a diaphram? It's a Mikuni VM24SH (2A000) according to the manual, that's if it's still the original carb.

I thought I'd sorted this but unfortunately not. I cleaned the carb again then fitted an inline fuel filter and clear fuel pipe. I've done a few 4 mile journeys, mostly low speed, with no problems. Yesterday I set off on a 30 mile trip. After a few miles, I was doing 60 when the bike bogged down and died. Again, if I waited a couple of minutes the bike started fine. If I kept the speed and therefore revs low all was well. If I went faster with the corresponding higher revs the bike would bog down then die within a mile or two. Each time this happened I checked the filter and fuel pipe, they were full of fuel. I think this rules out any possible problem with the tank breather and/ or fuel tap. I'm thinking it's a problem with the carb. It seems to work fine until it's asked to deliver more fuel, then fails. Does this maybe suggest that the float is set too low? If I measure it and find out this is the case, how do I adjust it? An other ideas?

I'm not sure really. When I put the carb back together the float was moving around at I expected it to, the pin was correctly located and the floatt needle seemed to be working well. I get your drift though, it does seem that everything is fine until a bit of petrol has been used from the float bowl, then things start going downhill.

I didn't touch the float height. Assumed it would be ok on its existing setting? Adjusting it is something I'd never done. The problem with the bogging down first happened having done around 15 miles on a dual carriageway at 60 odd, assume it would have happened earlier had the setting being wrong? Just checked the Haynes manual, it says the settings are factory ones.

Checked that. I had an earlier problem with the carb overflowing that was due to the float needle having a bit of dirt on it. The float seems to be working ok, to my inexperienced eyes at least!

Cheers I've already checked the fuel tap, it flows nicely, the fuel line between the tap and the carb is fine too.

I bought a 1982 model 5 days ago. Did 100 miles or so with no problems. Over the last couple of days I've had problems with it: It's OK from cold but after a mile or too the engine starts to bog down. You can't rev your way out of this and evetually the engine dies. If you leave it a minute or two it starts first kick then runs for half a mile or so before bogging down and dying again. Repeat several times. The bike had stood for a couple of years, most likely with an empty tank. I can see some rust in the tank. I took the carb off there were a fair few small rust particles in the float bowl but the jets were clear. The plan is to clean out the tank and fit an inline fuel filter. Thought I'd run it by you guys though, see if it could be anything else, in addition to the obvious dirty fuel problem. I don't understand why it starts so easily shortly after dying. Is it maybe that the rust particles settle at the bottom of the bowl, get agitated by the fuel coming in when the engine is running, temporarilly block the jet, then drop back down when the fuel stops coming in? Or something else? Also, would appreciate any recommendations as to which fuel filter to get/ not to get. Cheers.

Cheers for the replies. I have keys for the petrol cap and ignition, it's the steering lock and helmet lock cum seatlock that are missing. I think I'll try drilling out the helet/ seat lock, replacements are available on Ebay. I'll leave the steering lock for now, it's not locked so can ride it.

Lol I can see how it could be read that way! Bloke I'm buying it off bought it 2 years ago as part of a job lot, it's been sat in his shed since. I guess the ignition barrel must have been changed at some stage as the key for this doesn't fit the other locks. I guess brute force will do the job but would appreciate knowing a better way, if there is one!

I'm, shortly going to pick up a Yamaha RS125 I've paid a deposit on. There are a few issues to sort including no keys for the steering lock. Also no key for the helmet lock, this also locks the seat, it hinges on the other side. This one is important as I need to replace the battery, the 2 stroke oil tank is also under the seat. I think I'm going to need to break the lock, possibly replace it at a later stage (if I can get hold of one). I've never broken a lock before. Would a screwdriver in the lock held by a wrench or similar then forced clockwise do the job? Any tips on this?

Cheers I mentioned in the post that I'm in Cheshire, I'll have a look at my profile and see if I can put a location in there as well.

2006 42,000 odd km, red, MOT until mid September. After looking for a year I've finally found the 80's 2 stroke for me so my trusty GN is up for sale. I'm mature (55) so haven't thrashed the bike, not that there's much point in thrashing a GN. I've owned the bike for just over 6 years, it's been my only transport. In this time the only problem I've had was 4 years ago when a nasty top end noise developed. The bike shop replaced a worn rocker arm at no great cost. Since then it's had a slight 'tappety' noise. I've been told that a tappety engine is a happy engine. Maybe adjusting the valve clearances might solve this but 25,000 km on, it's doing fine. Negatives: The speedo doesn't work properly. These turn up from time to time on Ebay, 20 to 30 quid. There's some slight pitting to various bits of chrome. There's some rust around the exhaust rear bracket and the back of the rear carrier. There are 2 very small dings on the tank which you can find, if you look very closely. A little petrol exits the carb overflow pipe if you store the bike with the petrol tap on. None comes out if you turn it off. The gear position indicator sometimes works, sometimes it doesn't. Probably a loose connection but let's say it doesn't work. Positives: Recently facelifted with new mirrors, side panels, seat and rear shocks. The new shocks are firmer than previous as is the seat. This gives, in my opinion, a much nicer ride as previously it was a bit squashy and uncomfortable, if you went more than a few miles. Oil and filter changed every 1,500 miles since I've owned it. Both tyres new September 16. The Givi top box that's fitted is included in the sale. Overall the bike looks very nice for its age and even gains appreciative words from others which is quite surprising, as these bikes are nothing special. Other than what I've mentioned everything works as it should. I don't have the time or inclination to ask a cheeky price then reject a series of cheeky offers. It's a firm £650, no offers thanks. I think it's worth more, you might think it's worth less, that's fine, that's the price. The bike will be available in about 10 days, when I pick up my stroker. I'm in south Cheshire now, the bike will be stored near Stockport when I get my new bike. I'm a bit of a dinosaur when it comes to technology but if anyone wants a picture or two I can probably manage to send some to your email. Thanks for looking, happy to answer any questions.

Sorted! Thanks for the help.

OK I've fished through the used oil and found another part. Around an inch long, narrower and rounded at one end, wider and flatter at the other. I'd guess that the part I've just found goes in first, followed by the spring, but I don't know which way round to put the part I've just found. Does anyone know where I might find a diagram that shows this?

Yes a quick Google suggests it was probably the neutral stopper. Only a spring fell out though (I think), other posts on the subject said another part fell out too. If there was another part which I've now lost what might be the likely result?

I've just checked: I undid the wrong bolt! I've now pushed the spring back in, tightened the bolt then undid the correct bolt, which allowed more oil out. I'm nervous though. Do you think this will be ok?

I've just undone the sump bolt on my GN125 to do an oil change. I've done this many times before, no problems. Today when I removed the bolt a spring, around 1 inch long, followed it. This has never happened before. The diameter of the spring is less than that of the sump bolt, I'm pretty sure it's nothing to do with the bolt. My best guess is it's something to do with the clutch that may have fallen off? If so, why didn't this get caught up with the gears and wreck the engine? Any ideas? Do you think it might be ok to do the oil change as normal, leave the spring out and see how I get on? Any advice at all? Cheers

I'm in the process of doing up my GN125, it's rather sad and rusty. Most of the parts are easily available, and cheap. The exception is the chain guard, which is difficult to find. My thinking is to remove it and rub it down, apply rust cure then etch primer. I'm thinking of a matt black final coat. Any advice on the best black paint to use? Cheers.

It's difficult to describe the leather, the usual stuff sofas are made of. Fairly low quality, I'd guess? Might vinyl be a better choice? The seat is 'stepped' in that the back half is maybe an inch higher than the front part.

My GN125 seat cover has a couple of big rips in it. I've got hold of a piece of black leather off an old sofa that's big enough for the job, was thinking of having a go at it. Is it best to stretch it as tight as possible over the existing cover then simply staple it to the base of the seat, or would it be better to remove the old cover first? Any other tips? I'm not looking for a 100% job, half decent will do. Cheers.

My GN125 is from 2006, 30,000 miles on the clock. A couple of years ago the engine developed a nasty top end noise when I was on a motorway. Not feeling too confident working on bikes myself at the time, I took it to a bike shop. The problem was a worn rocker arm, which they replaced. Ever since then there's been a slight top end rattle, best described as tappet noise. The bike shop assured me the valve clearances were checked and this noise is normal with small engines, when they've done a bit of work. The bike has been reliable since, despite the noise. I'd quite like to get rid of it though. The noise that is. A couple of questions: Is it normal for an older engine to become more noisy? The valve clearance range on this bike is quite wide. Generally speaking, would a bigger or a smaller gap tend to cause more tappet noise? I guess I'm thinking along the lines of adjusting the clearance to close to the specified limit, bigger gap or smaller gap, whichever one makes the engine quieter. Cheers for any replies.