Waynetod

So, I'll just drain the tank and run the carb dry before standing it down until next it's used. Seems a lot easier to do this. I hope I haven't stirred up a hornets nest by asking about ethanol effects. ?

So, it's a case of buying Shell ultimate or Esso synergy supreme plus. As long as you live in the right area. I've been putting "Briggs & Stratton Fuel Fit" in my mowers for a few years now. And also in my kawasaki W800 over winter. Maybe it's time to find an ethanol stabiliser to add to the fuel.

Thanks for that. I'm old school and wasn't sure if modern fuel tanks could accept ethanol in fuel.

As I'm about to pick up a 2016 Scorpa ty125 4 stroke, I was wondering how everyone with modern plastic fuel tanks get on with fuel that has 5-10% ethanol, which, in the UK, is the most common type of pump fuel. Or does everyone use specialist fuel like Aspen4T or Stihl4T. Expensive at £20 for 5ltrs. Just worried that plastic tanks and carb seals won't swell up with modern ethanol based fuel.

Whoa! Handbags at dawn ladies. Let's move on?

Welcome. I've a few dumb ass questions I've got to get to asking?

Welcome.

Hopefully, when I repack the exhaust boxes, and change the fork seals, I'll have a runner that can be used. I just hope the exhaust clear out will allow it to produce a bit of power as it starts and ticks over fine.

Hi Keith. When I've sorted a few issues with the Montesa, I'll be up for a ride.

Thanks everyone. Looks like I'll be giving the exhaust boxes an opening up. Rear box and centre box. They've never been done. I'll speak to the owner first, before cutting a hole in either, then repacking and plating over.

Was it running crap on wider throttle openings before you cut them open, and was it running better afterwards?

Thanks for the reply. Will look into cutting it open.

Hi all. Can someone tell me if the back box on a 349 (year around 1980?) is the only part that needs a decoke? That flattened part of the exhaust under the tank, does that contain baffles too? How would both be done? Bike starts and idles great after a thorough carb clean and rebuild, but feels like the baffles are blocked on wide throttle openings. I've done the caustic soak and a blowtorch up it's back box, but I'm still having an issue when get on the power.

Thank for the replies both. If I get it running right Keith, I'll be up for a ride. And Lowbrow, I've rebuilt the carb and it's as clean as clean can be. I've had all the jets out, and there's no crud whatsoever in there now. Clean as a new whistle. It starts first kick, with choke, from cold, and first kick without choke when hot. It idles beautifully, but its not right on wide openings. I may try different needle heights to see if it makes a difference. It feels like the exhaust wants a decoke. I've flushed the back box out with caustic solution, and left a blowtorch blowing through it for a hour or so. It still feels the same. I've tried it without the back box and it's bl***y loud, but still the same. I'll ask in the fixit section for suggestions.

Hi, my name is Tod, and after 40 years of being without a trials bike, I'm now back in the fold. I've never been without at least 1 road bike and recently managed to blag a long term loan of a Montesa 349, of the type I used back in the day. Been fettling with it to get it running after being laid up for at least 2 years. And now it starts 1st kick and idles sweet. Just have to figure out the other big issue..... Poxy thing is stuttering in wide throttle openings. No power. I'll be scouring this site for solutions to this problem, and probably solutions to problems I don't know about yet.