i am getting low end bog -------once the rpms get to about 2800 it starts REALLY pulling. how do i get rid of the low end bog though?

 

Have to hook up the accelerator pump to get rid of the bog completely. Running a little bigger pilot or raising the needle a groove may help without the pump.

 

i really, really wish people would STOP selling these carbs without the accelerator pump completely intact. Places sell these carbs knowing there is some dificulty in setting up the pumper, so sometimes they just remove some stuff to deactivate it, and then when somebody wants to make the carb right they are missing stuff sometimes. Fact is - to deactivate the pumper all that has to be done is to slip the spring off the edge of the plastic actuator - no tools even required!

But anyway, to answer your question bigshow - the TM45 is equipped with an acclerator pump and it needs activated and tuned as DSRyder says. There is a white plastic piece on the right side of the carb that rotates to push on a rod that extends down into the carb bowl and pushes on a plunger to squirt fuel into the throat of the carb when the throttle is opened from idle. You have something disconnected somewhere, or maybe even pieces missing, that will need corrected before proceeding with tuning. once you have everything put together right, the pump nozzle you need to install is #50, your carb prolly has a #70 in it now but it is too big. *You need to see a post entitled TM45 w/ accel pump made easy for thumb throttle to get a grasp of how the spring setups work.* You need to order a #50 nozzle, some pilot jets - maybe a 25 and 30 to start, the pumper spring if its missing + whatever else may be missing, the light throttle return spring if using with thumb (which you prolly have already on the carb), or the heavy throttle return spring for use with twist, and the TM45 tuning manual - all available from RWR.

 

Actually, to add to that, you need to seal the hole where the pump rod goes in to. Either with silicone or by bolting a screw from the bottom. [img]i/expressions/face-icon-small-smile.gif[/img]

 

No you don't Tyre - you leave the pump rod in, don't remove it at all, then there is no hole to plug. just lift the seat on the bike, flip the spring off the actuator with your fingernail, and the pump does nothing from there on out. There is absolutely no reason to remove anything, or butcher anything like so many have done in the past. It really is that simple.

 

.

 

I need to clarify and appologize for this statement - I actually don't know what the "deactivation" practices are of the dealers who supply these carbs - I only know that more than one person who has attempted pump activation has found that parts were missing, but this could very well be the result of a previous owner passing down a second hand carb, and not necesarilly the practice of any carb dealer/distributor.

As far as why they ever get deactivated - the only reason I am aware of is to reduce thumb throttle tension by replacing the return spring with a lighter weeker spring, which in turn is incapable of overcoming the pump spring and doesn't allow the throttle to fully close back down to idle. So if you run twist throttle, the stock heavy spring can be used for trouble free pumper use, but to use thumb throttle and pumper requires some inginuity in spring altering to create a spring that is easy on the thumb, yet still operates correctly with the pump.

 

All,

I've been doing a lot of thinking about this problem with the pump. As some of you know, my old mechanic (as well as others) broke the secret on the TM45 carb pump over a year ago. I had paid him to work on it for nearly a week to figure out what needed to be done to get it to work on the Rotax motor. For a time, we had an exclusive as far as people that were offering the TM45 fully tuned with the pump.

For the last two months, my old mechanic decided (for whatever reason) that he didn't want to offer this service anymore. I must say, he was incredibly loyal and told nobody the measurements to make the TM45 pump work on the rotax motor. Its something that I invested a lot of money for him to figure out. And, the service really helped a lot of DS owners out for nearly a year.

However, since my mechanic stopped offering this, I felt I had an obligation to pass that information on to the next logical source. I truley believe, like Hightower, the TM45 is one of the best carbs out there for the money. So, since its important for all riders, especially future TM45 owners, I have instructed my old mechanic to give those measurements to Elliott of Ron Wood Racing. As of late today, Elliott, and any Ron Wood Racing dealer will now be offering the TM45 carb with the pump activated and properly tuned with any carb purchase (if they ask for it). And, since RWR can adjust the pump, rather than remove it, there will be no extra cost to those that buy a new carb. Turnaround time now is also reduced.

So, that's the story.

marky

 

so Marky what are the recommended settings??

 

I dont have them written down. Its something my old mechanic had in his head. Basically they are settings measured via caliper to set the two adjustment screws. You can ask Elliott.