bfa

SOLVED! Dielectric grease on the contacts on the 32 pin connector seems to have fixed it. The symptoms indicated electrical (and all other aspects of the engine were 100%) and it appears that it was just a matter of poor contact somewhere. Thanks for your input!

Cold start: idles okay, I don't touch the throttle until the engine has warmed. Otherwise it runs poorly above idle.

Thanks for that! I will check it out. My first impression was that it could be an electrical issue, so I tested the resistance of most of the main components and they were all within spec. Also installed a new spark plug. Good suggestion, and I am also going to check the spark plug cap while I am at it.

Even warmed up to where the fan is running continuously it will not rev without missing and worst at rev limit with smoke and popping. Pops while riding, even on open straights. When cold, it will start easily.

Cool but not stone cold. After I bump started it, I ran it for a bit, shut it down tried to start it again, same problem (x2).

My '09 4RT will start easily from cold and most times after having run. Whether it is after warming up from a cold start or in the middle of a ride, it idles smoothly but when the revs pick up it misses and pops. We are at 3000 ft. elevation and the other day rode up to 8000 ft. I started it easily to move it just a short distance, shut it off and then it would not start except by bump starting and it ran very poorly at that. It is rideable but performs poorly. Any suggestions where to start looking? Thanks.

Using stainless steel oil filters means you don't have to throw anything away but broken down oil. The Monty uses the same filter as the CRF 250. They have really dropped in price. The newer high quality oils, especially synthetics, tend to break down slower. It would seem that we tend to be over-cautious, but for the little effort it's good assurance to keep it up.

The manufacturer (Montesa) recommends using motor oil for the air filter. Does anyone use air filter oil products like No Toil or Motorex? Is this a good/ bad idea? Thanks.

Wow, that's impressive. How many times did the valves have to be adjusted?

I was thinking of using the Nutech Tubliss system on the front. It works great on the front and rear of my enduro bike and thought it made sense to use it on the Monty. Full circumference rim lock! Any thoughts? BFA

So, why are the front tires on most trials bikes tube type and not tubeless?

Thanks folks, I feel much better now. Time to ride. Regards, BFA

My new 2009 4RT is overheating and my first thought is compression ring blow-by until the ring seats. As an example, I start the bike, warm it up for a few minutes, get up to fourth on a very gentle uphill grade, go about 300 metres, turn around, come back down the street against the breeze and half way back the fan comes on and the engine is HOT. I bled the cooling system to be sure there was no airlock. Should I be looking elsewhere? Thanks.

Hopefully I am getting a clearer picture. If the previous models did not have the O2 sensor and the throttle body does the monitoring of air density to create a closed loop system, then the O2 sensor is simply for emissions reduction (minor as it may be)? If so, then the catalytic converter with O2 sensor were obviously included solely for use with the street legal kit (not valid in Canada or the US). Thanks.

I have an '09 4RT "Repsol" and am going to be riding through elevation changes of 6-9000 feet. If I do the complete "full power" mod (factory), it involves exchanging the header for one without a catalytic converter and removing the oxygen sensor (no port). Does the removal of the sensor make it an open system? Will the fuel injection system have difficulty adjusting for significant climatic changes? Quickly or at all? Does it affect fuel consumption? Thanks.