DJYAM

I am not arguing anything. I am simply responding to suggestions that I have already confirmed are not issues. No need to be sarcastic. It's been suggested about cleaning jets multiple times, which I have done. Checking for leaks, which I have done. All mentioned in the original post. I have asked multiple questions regarding float height etc with no direct response, just more nonsense. Answers about 2T and jet kits aren't helpful for obvious reasons. The ONLY thing I can think that is suspect, is there is a carb balancing 'port' on the engine side of the carb, which to my knowledge needs to be sealed, and is. With a fuel line and some glue, 100% sealed. I am not aware of any other 'air bleeds' that need to be open/closed. I do understand the physics of a carb, I have spent a long time making adjustments to them in the past. The questions I've asked about being too rich, but only running in this state haven't been answered. Howcome it runs relatively well when rich, but not at a 'normal' mixture? This doesn't suggest that there is a fuel blockage.

It's definitely clean, I have been through it multiple times. This still doesn't explain the rich running, as surely if a jet was blocked, it would run ok with slightly bigger jets, to get the same amount of fuel, not huge jets.

The idle jet is now 55, and the main 140. This is running way too rich, but seems to run better with less bog. So why can't I reduce bog with smaller jets, seeing as it is now running rich? Changing needle height didn't seem to have much of an effect at all. Float height? I've tried a few different ranges and not much difference noticed.

Yes... As I said, tried multiple sizes of each jet, all clean.

So... I tried a much smaller main jet, no better. So the next step was a much bigger idle jet, bogging was reduced by a good amount! Still slightly bogging, but much better. The problem now is, the bike is running way to rich, white exhaust smoke, excess fuel in carb-engine manifold, black plug. So what now, because reducing jets just seems to create bog? Is the carb just not suited to the bike?

It's not 2T. I have a bunch of jets already, just not below 100 as stated. I assume a 100 jet in one carb would provide a different mixture to the same jet in another, due to air flow and carb design?

Can anybody advise on jet sizes? All kits seem to start at 100 for the main, does going smaller than that seem like an odd thing to do? Could the carb just be too big for the bike?

I've checked for for air leaks, all ok. Slide keihin carb. Any place to get jets that isn't China? Delivery is shocking at the moment! New ISH plug. Previous owner was that silly bugger unfortunately, hence why the carb isn't standard

Also, the bike seems to have a rev hangup. If I raise the revs, they take a long time to fall back to idle.

Hi all, Thanks for the help previously, much appreciated. I have recently acquired a Yam TW125 for some green-lane fun. Bike starts fine and seems to idle OK too. When building revs very slowly the bike seems to reach max with no issue. When opening the throttle fast the bike bogs down and dies, unless I let off immediately. The plug was quite sooty, I thought it must be too rich. All of my research however tells me that my symptoms are that of a lean bike and I should adjust float hight. I have been experimenting swapping multiple sizes of pilot and main jet. Just swapped to a larger main, 120, and noticed fuel coming from exhaust, must be too rich. The base main jet I started with was 100, now I want to reduce to 90 ish, does this sound small? I know it is dependent on airflow but standard jets all seem to be 100+? The air flow on the bike should be good as it has an aftermarket exhaust and filter. Ps. Float height has been adjusted in both directions, neither seem to help, and definitely do not cure the issue. So, does bogging sound like a rich bikes problem? Is sub 100 main jet size small? Anything I'm missing? Thanks in advance

Sorry for so many messages. I have found an exhaust that has the 2A6 code instead of 2A8. Says it's from a 125 or 175 mx. Is this the same exhaust? Not sure what the number means. Mine has 'YAMAHA 2A8-14610' This one has '2A6-14610' No YAMAHA print. Looks genuine though. (old and dented/used)

I did consider taking it to a welder, I thought by the time they had done, it may cost as much as buying one. The crack goes all the way round the tube. Maybe I should buy one for now, as I shouldn't ride it like that. And see if someone could repair it for a spare or to sell.

Haha! I think I have, haven't I! I assume these are just prone to rusting and breaking in these places, due to it being a U bend and the shaking stress. Wow, that looks to be solid. I found one for 300£ yesterday but wanted to ask in case I was about to pay way too much. Hmm, 175 any more findable? I suppose not if there the same. Thanks guys

Hi guys, I have just finished restoring my DT125MX and it looked lovely. Rode lovely. Yesterday I started it and noticed that it was much louder, sounded like the exhaust blowing. I unwrapped the exhaust tape to unveil a gaping crack round the exhaust where it drops and bends out of the engine. I have been looking for exhausts online and have seen a few. Front ends! Is the 125 the same as the 175? Or is someone looking to get rid of one? Or know who is? Cheers. Dan.

Yeah, I had noticed that the panels are a slightly different shape! I also ordered a new pair which have a hole in the side, looks like it is meant for a fuel tap? Unused on my bike! Do you know anywhere I can buy the US stickers or should I buy the UK ones? Thanks for the help.