July 27, 200422 yr I recently purchased a 2000 Cota 315 in beautiful shape but not without a few (hopefully) minor issues. In the past I have owned a Cota 247 and an Ossa MAR but it has been 20+ years since I have had either of those. My plans are not to enter competition but just to enjoy having a Trials bike once again and to help keep my reflexes and coordination from going completely south as I get older. One of the things I noticed immediately when riding the 315 for the first time was that it didn
July 27, 200422 yr Cody: Welcome back to trials riding! That Barbour suit and full bore boots will come in handy. Fashion Smashion! The idle issue may be improved by fiddling with you air screw and speed screw. Just ck. to see where it is now and then play with it. Also The size of your pilot jet will have an effect on low speed smoothness. You don't say where you are located. It's consideed a common courtesy on here to adjust your setting profile to show folks where you are from. Anyhow find out what size pilot jet you have and call up your Montesa dealer or importer to find out if the jet is the recomended size. Beyond that you could have a sinking carb float or incorrect float level adjustment. My guess is fuel mixture fine tuning will resolve your problem. Have fun, Jay
July 27, 200422 yr Author Hello Jay, Many thanks for your thoughts and suggestions. First off, I certainly didn
July 27, 200422 yr in my 2002 montesa i run 110:main jet 35:pilot jet air screw :3 1/4 turns out i hope that this helps
July 27, 200422 yr Kind of went through the same thing you are experiencing when I returned to the sport a few years ago. I learned on a Bultaco Sherpa T with lots of flywheel etc. I bought a 2000 GasGas and it took a while to get used to the modern technology. I made a few adjustments to the bike that tamed it down and made it fun to ride. First off, make sure you've got the slow, throttle tube in (black if Domino). I switched to a rear sproket with 3 extra teeth. In retrospect, 1 less tooth on the countershaft sprocket would have been better, but if I'm not mistaken Montesa's have only 10 t stock. I then retarded the ignition timing by 1 mm. There have been several threads on this subject in this Montesa board, do a search for all the specific how to's. The overall effect worked great for me, a senior novice. You will still need to learn how to work the clutch in the sticky, tight stuff, as the new technology does require a different approach than vintage iron. After getting used to modern bikes in general, I had an opportunity to test ride a 1998 Montesa and found the power to be very smooth and managable.
July 28, 200422 yr Author in my 2002 montesa i run 110:main jet 35:pilot jet air screw :3 1/4 turns out i hope that this helps Hello Landrover, I wonder if the carburetors are the same for your
July 28, 200422 yr Author Hello Eric23, I always loved the looks of the Bultaco Sherpa T but never had the chance to ride one,; it
July 28, 200422 yr Cody: I'm certain the 2001 and 2002 do not use the same jetting as the 2000 cota. There was a post previously in which our US Montesa importer gave us the correct jet sizes. I wish I could recall what they are. Don't feel bad Land Rover I know just how you feel. My 2001 ran a 39 pilot, 7/8 turn out and 110 main and a cut out airbox lid. It ran awesome! I never had an older Montesa unless you count the '84, the 86 and the '88.
July 28, 200422 yr Author Right you are Jay about the different carbs, in the archives I just found a post made by t_whimp on 3-26-04 with a response from Mr Martin Belair as follows: "t_wimp, your bike should have a Dellorto PHBH 26CS. The Montesa carb was changed in 2001 to Dellorto PHBL 26BS. The jetting is not the same for these two carbs. For your carb the 44 pilot is good, the main jet should be 125 -128. This will get you close. The rest will be fine tuning. Are you using leaded or unleaded fuel? Martin Belair US Montesa " (end quote) This is the same carb that I have, and although I don't yet know what the existing pilot jet may be, in my spare parts bag I do have a new #44 jet to try. Now, if I can just get my left wing to work correctly so I can work on it!
July 28, 200422 yr Cody, chances are that your bike is jetted correctly. I suggest that you try lowering the gearing to get the performance that you are looking for. Sprocket Specialists can supply you with any size sprocket. I suggest that you add 2 teeth (from 42 to 44). I have found that many riders that are used to vintage bikes find this to be a good solution. If you ever decide to try and change pilot jets (there are 2) please be careful and use the correct size screwdriver. It is possible to damage the carb and get the pilot jet stuck by using the wrong size screwdriver. If you have any questions you can always call me at 952 937 8720. Martin Belair US Montesa
July 28, 200422 yr Author Hello Martin, Many thanks for your thoughts and the heads-up regarding possible carb damage while changing pilot jets. My plan, as of this moment anyway, is to pull the carb and give it a thorough inspection just to make sure the pilot jets aren
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