247T Cota Manual

[David Lahey]

There may be something wrong with your bike because kicking over a 247 is not mormally a big deal for people of average size and weight. You do need to get your body well forwards of the normal riding position before starting to push on the kick lever.
How about you post up a photo of the RH side it and we might get some clues as to what is going on.

[David Lahey]

The gear shift position is going to drive me insane - can I move the foot pegs - or do you have any other suggestions

Thousands of people throughout the world can quite happily ride the Cota 247 with the gear lever and footpegs in the standard position. Almost every other trials bike is the same in that regard. You will probably get used to it sooner than you think.

[keychange]

David - today is my second day still raining heavily (and I am supposed to be working !!) so limited time to test but yes I think I can get used to the gear position - although considering the "T" stands for trail it would never do in a tight fast run.

This photo http://www.red-devil-racing.com/images/montesa_07.jpg is my actual bike advertised 2 years ago - I found it while browsing today - the bike looks much the same but maintenance has been neglected (maybe they had the same problems I had reading the manual). I removed one of the plugs and I can kick it over with my arm - but with full compression it takes all my weight to move it and I am 80+kgs. Over the years I have kick started DR650s even a Harley 1200 and this seems just as daunting, I put it down to the short kick lever - but seriously my 50 kg wife would bounce on this all day with no hope. Seriously I have to launch up and full weight down to get it past the compression stroke - my right leg quad is sore, no kidding.

Once started the bike feels fine plodding around - engine is strong and tractable up to around 3000 rpm but it flattens and dies at something around 3500 rpm (guessing), just when you feel it should take off - is that the trials expansion chamber? - to me it feels like air filter - will check tomorrow.

I remember back in 70's we used to fit decompression valves to the second plug - but that shouldn't be necessary to a 30+ year old 250 two stroke =- should it?

[David Lahey]

David - today is my second day still raining heavily (and I am supposed to be working !!) so limited time to test but yes I think I can get used to the gear position - although considering the "T" stands for trail it would never do in a tight fast run.

This photo http://www.red-devil-racing.com/images/montesa_07.jpg is my actual bike advertised 2 years ago - I found it while browsing today - the bike looks much the same but maintenance has been neglected (maybe they had the same problems I had reading the manual). I removed one of the plugs and I can kick it over with my arm - but with full compression it takes all my weight to move it and I am 80+kgs. Over the years I have kick started DR650s even a Harley 1200 and this seems just as daunting, I put it down to the short kick lever - but seriously my 50 kg wife would bounce on this all day with no hope. Seriously I have to launch up and full weight down to get it past the compression stroke - my right leg quad is sore, no kidding.

Once started the bike feels fine plodding around - engine is strong and tractable up to around 3000 rpm but it flattens and dies at something around 3500 rpm (guessing), just when you feel it should take off - is that the trials expansion chamber? - to me it feels like air filter - will check tomorrow.

I remember back in 70's we used to fit decompression valves to the second plug - but that shouldn't be necessary to a 30+ year old 250 two stroke =- should it?

It looks like a 250cc motor to me in that photo. Maybe someone has fitted a different head which raised the compression. If you can find some one nearby with anoither 247 you will be able to compare them.
To make it easier to kickstart, ease it over compression then let the kickstart go back up again. That way the motor will start spinning before it gets to the next compression. I do that with my 348 to make it easier, and it has the same kickstart arrangement as the 247. No you shouldn't need a decompressor to start it.
It sounds like you have not ridden a trials bike before - or maybe it is just an April Fool's day joke, but trials motors are meant to have a flat power curve. They are not meant to "come on" or "take off" at any RPM. If it four-strokes as the revs come up then yes there is probably something wrong.
You have been decieved by the T in the model designation. The 247T is the same bike as the pure trials version except for the seat/tank unit so it will never be anything like a motocross, enduro, or trail bike to ride. You may find it can do reasonable times in a tight fast run through the bush though, because you will find you will rarely have to change gears anyway. On that bike it would be 4th gear all the way. Third will be too low and fifth too high for that sort of stuff. I have been known to partake in the odd drag race on my Cota 348 and provided I start in fourth gear (it has six gears) it puts many supposedly fast dirt bikes to shame (for the first 50 metres) thanks to the very heavy flywheels, a gutsy motor and a practised use of the clutch.

[keychange]

No April fools joke and correct I haven't ridden a trails bike for nearly 40 years but I have ridden countless other bikes including Bultaco 315 it was nothing like this. I can't get it past the compression stroke without an almighty heave - I am scared that I am going to strip the kick start spline - I am not kidding it is that hard to kick. With the spare plug removed it turns over easily. Could it be a blocked exhaust??

Cheers

Andrew

[David Lahey]

If the exhaust was blocked the motor would not run and you said you have had it running.
It sounds like your motor for some reason has a lot more compression than the 247s I have ridden. One thing you could do is take the exhaust header off and have a look up into the head through the exhaust port to see if there is something strange there - like maybe a lot of carbon buildup.
Another thing that can make a bike hard to kick over is if the crankcase is full of petrol but again you said you have had it running so it doesn't sound like that is the problem.

[keychange]

Exhaust is clean and crankcase has been drained twice (if crankcase was issue it wouldn't turn over easily with plug removed) - it's compression but I can't for the life of imagine why it is so high. I will seek out a decompression valve, any ideas on where to source one is appreciated

Andrew

[keychange]

A bit of water in carbie float bowl has improved go but it is still badly lacking revs ( and please don't say it's a trials bike) - I know what a 250 should feel like and this simply dies on open throttle. Having flushed the tank and cleaned carbie I must assume it's timing or points or both. I know it has a magneto - but the manual doesn't show where it is - I am a guessing behind the right hand crank case cover - do I need any special tools to get the magneto off?

[keychange]

I have pulled the magneto off - cleaned and set the points - then advanced the timing about 5 to 10 degrees and that has solved the start problem - it starts first kick almost every time. Still dying under max throttle so I fiddled with the jet needle it was set middle so I tried moving up and it made things worse so I lowered it (leaner) and it has improved quite a bit (air filter has been cleaned already) - I reckon I am getting about 90% of the power I expect and it's only the last half inch of throttle that she stutters on so I will take a closer look at the main jet - I think I am getting somewhere and I certainly know a lot more about my bike now. BTW - since you can't change the timing with the magneto on - is it just hit and miss or is there some other trick that will let me run my timing light and adjust on the fly?

Cheers

Andrew

[keychange]

I know I have mentioned elsewhere but just to close off this post as it was asking for information and I drifted into specifics.

I fitted the compression release and starting is now a dream. The compression tested at 135 psi - which sounds ballpark for what I'd expect. Performance is much better than originally - almost there, but I have ordered a full carbie kit from Amal UK - just weighting for Iceland's volcano to let the planes fly.

The shocks are all re-rubbered and held on with bolts as well as circlips. Seat pan is repaired and looks ok, speedo repaired, cable replaced and working fine, broken rear mudguard repaired and looking ok, broken foot break replaced, exhaust remounted and muffler joint replaced (I have used metal sleeve rather than rubber original I hope that is ok).

Yes I am getting used to the gear change but if I don't get bitten by the trials bug - to use as a trailie I will change the rear 48 tooth cog for the original 40 and get some use out of 4th gear.

So I think I have the engine sorted (fingers crossed) and now just need to either get the rear wheel hub rebuilt (taking to a Cota expert on Friday) or buy a second hand unit from USA - $20 for the part and $55 for the postage

It's all nothing less than I expected - but I do hope I get a chance to ride it seriously one day - soon... thanks for your help.