arfur

Hi Dave, Stripped the carb today and it has a 140 main jet, 35 pilot jet and could only find a U on the needle so no idea what size that is. I guess the main being smaller will cause it to be lean on high revs? Thanks Arfur

Hi Shaun, That's the Spanish site I found. I'm in the UK so will give the InmotionTrials a call on Tuesday. I'll put some pictures up too. Thanks for your replies.

Thanks P@ul250 Perfect, I'd found a site in spain but a UK one is much better. It's 1978 Cota 247 that I have.

So I've managed to split the intake spacer between the carb and cylnder block. Does anyone know where I could purchase one? Alternatively is there a heat resistant glue that i could use to repair it? Doh, Doh, Doh....

Stripping the bike down today. Removed the carb and I am getting more blowing than sucking on the inlet. This doesn't sound good. Are there reed valves on this engine? They are not between the carb and the block. Could thus be really bad crank seal leaks? Lots of oil in the exhaust system too!!!

Hi Bambam-n-chunx, I have just got my hands on a Montesa Cota 247 with the frame number starting 21M26 something or other and am trying to gain more information and came across your post. My carb too is a 627/450 and wondered if you have any more information about it and other parts of the bike as all the manuals etc. that I have found atop at 1975. Any info you have would be greatly appreciated. Thanks Arfur

Thanks for all the responses. The oil I am currently using is Central No Smoke Oil !!!! Again this is what the previous owner used. My plan now is:- Change the oil in the clutch and gearbox so I know exactly how much there is. Then I can monitor if I am losing any through the seals. Drain the petrol tank and then use some fully synthetic oil, but not going too lean. Strip the carb and clean it. I have found a number of manuals for the Cota 247 but they all stop around 1975, is there one for the 1978, it is a 21m26000. Just want to be armed with the correct information before I go diving in.

Uh oh, that doesn't sound too good. Is there a way of checking the crank seals or is it a strip down job?

Hi All, I have done my first trial now and have a few issues with my 1978 Cota 247. It smokes a LOT. It dies at low revs. It feels all choked up. The person I bought it from said to use a ratio of 25:1 and it is a mineral oil Is this the best oil to use or go to a synthetic? Is the ratio correct? I will go and pull the plug soon to see what it looks like. Is it worth pulling the exhaust off and clean it out? Is the gasket on the exhaust re-usable or will I need a new one? Sorry about all of the questions, but you guys look a friendly bunch.

Thanks for the reply Dave I was intending to join the Dabbers as they come highly recommended and are quite local. Unfortunately I am already busy on the 19th but will do my best to make the next one.

Hello there, I have just acquired a Montesa 247 COTA with a little research I think it is 1978. I have had bikes on the road for many years but this is a new venture for me. Looking at some of the stuff on here I have much to learn before I even leave the garage for the first time I'm sure I will be back with the many silly questions but thought I would ease myself in slowly first.