carb problem on a 200

[johnkiely]

Hi guys,restored a 200 using 175 carbs and is suffering from fuel starvation,the parts book says the needle valve and slide are different but does not give size or number,so does anyone know what exactly I need to convert these to suit a 200.
Thanks,
John.

[rocketman]

Wheres it starving? Just on top,or all the way through?

[v330123]

JOHNKIELY:

I bought new 175 carbs from Richard Clark for my BS200 project. Richard told me that they'd need alternate main jets installed, and he included the right ones for the 200. I installed them, but really couldn't see much of a difference from the ones that came in the 175 carbs. The difference may be too small for me to detect with my eye, but significant to proper fueling. Whatever, the result is good, the bike runs very well.

My parts book (Certified Parts Corp.) does show a 90 and 95 Main Jet, but it doesn't say which is for the 200 or which is for the 175. It does show some other differences too. But, the book only shows one Jet needle.

I bet Richard can tell you what you need to change on the 175 carbs to make them work on your 200. The Main Jet that Richard provided is the only thing I changed. Good luck.

Gary

[rocketman]

 I'm with Gary,Richard should be able to help you both with the parts required and the knowledge as well. Going up on the main jet will most certainly be required for top end performance. Depending on what kind of riding your doing,the differences in the factory set up of the carbs may have little effect on the bottom end performance. Since the 200 requires more air,the slides are cut harder. More air usually means more fuel,thus the difference in jet tubes and main jets. On the bottom end,raising the needle can make up for some of the jet tube difference if you don't change them. If you go up with the main jet for top end,after a point you might find that you will have to drop the needle to limit the additional fuel on bottom end. The main jet called for in the 175 is a 90 and a 95 for the 200. My 175 service manual lists a 100 main as factory supplied in the 175DT...Typical.  Jetting is subjective and properly done requires a proccess.  Good luck,and let us know your outcome.  Mark.