<div class="FTQUOTE"><begin quote>Originally posted by: 00XJ

23mm? And the Jetmoto has a 30mm? IMO it is clear that "they" built this thing for top speed... bragging rights, etc... </end quote></div>

I dont think bragging rights came into play. LOL [img]i/expressions/face-icon-small-happy.gif[/img][img]i/expressions/face-icon-small-happy.gif[/img]

The 30mm carb is also used on the 200 and thats most likely why they used it. The 150 uses a 27mm version of the same carb. I dont think this engine is over carbed.

 

<div class="FTQUOTE"><begin quote>Originally posted by: mywifesquad

<div class="FTQUOTE"><begin quote>Originally posted by: 00XJ



23mm? And the Jetmoto has a 30mm? IMO it is clear that "they" built this thing for top speed... bragging rights, etc... </end quote></div>



I dont think bragging rights came into play. LOL [img][/img][img][/img]



The 30mm carb is also used on the 200 and thats most likely why they used it. The 150 uses a 27mm version of the same carb. I dont think this engine is over carbed.</end quote></div>


I'm going at this from my muscle car experience. EVERYONE had to have the biggest Holley they could get. Bad mistake, the car actually ran worse. Perfect example is the Quadrajet carb. The vacume secondaries would open up all the way too soon, and that caused the ledgendary Quadrajet bog. To much air for the engine to injest, and it would stall momentaraly. It could be fixed by shortening the accelerator pump rod slightly to pump more fuel.

I've found if I open the throttle up quickly, the engine on the 250 will do the same thing. Sometimes the bog is halfway up a hill. It will make it, but it shouldn't do that. I would love to try the 27mm carb.

 

<div class="FTQUOTE"><begin quote>Originally posted by: 00XJ


I'm going at this from my muscle car experience. EVERYONE had to have the biggest Holley they could get. Bad mistake, the car actually ran worse. Perfect example is the Quadrajet carb. The vacume secondaries would open up all the way too soon, and that caused the ledgendary Quadrajet bog. To much air for the engine to injest, and it would stall momentaraly. It could be fixed by shortening the accelerator pump rod slightly to pump more fuel.



I've found if I open the throttle up quickly, the engine on the 250 will do the same thing. Sometimes the bog is halfway up a hill. It will make it, but it shouldn't do that. I would love to try the 27mm carb.</end quote></div>

All that I understand.

Have you tried this with the larger jets? I got rid of all bogs with larger jets. I even put the jets reccomended for the 250 in the 200. It runs much better. i think its starving for fuel, not choked by fuel. The stock Jetmoto quads are set up very lean to pass the CARB certification in CA.

 

You might be right. Although I did put in the replacement jets Raceway sent me. Have you tried even larger jets? How about raising the needle a notch? Wouldn't that give it a shot of fuel quicker off idle? I've never looked at the needle, I assume it has other notches.

All this is mute point as of now, as I STILL can't ride the thing. I go to Jetmoto's website, and it states they have 10 rear shock linkage assemblies in stock, and 6 front shocks, yet going on 2.5 weeks later I still don't have my replacement parts. I'm beginning to get p***ed!

Sorry the venting was off subject, but I purposely got the ball rolling on these problems several weeks ago knowing I was taking this week off on vacation. Now the week is wasting away, and we can't get out to ride.

 

I believe they are raising the needle to the highest setting.

-JNY

 

<div class="FTQUOTE"><begin quote>Originally posted by: pimpsmurf

I believe they are raising the needle to the highest setting.



-JNY</end quote></div>

Ok I've raised the needle to it's highest setting, meaning the e-clip in the lowest groove. We'll see how it goes. Maybe all it needs is a shot of gas earlier.

Just a little FYI, Be careful not to pinch off the crankcase vent hose if you have it setting on a board raised with a jack. I couldn't figure out what the hissing noise was when I shut it down. DOH![img]i/expressions/face-icon-small-blush.gif[/img]

 

I took off the exhaust pipe and found a huge weld restrictng flow where the pipe bolts to head. I think the weld was atleast a 1/4" high all the way around the pipe. I ground the weld down and polished it up. I also looked into the muffler, much more restictive than on my fmf's. after removing some packing and cleaning up the pipe it has much better throttle response. I,m sure it could take more fuel now so i need to rejet it . Also the valves are way to tight from factory and need to be adjusted also. A better pipe and silencer would help if you can find one that would fit.

 

I took the headpipe off this afternoon, and found a slight "bump" from the welding. Other than that it was clean and smooth.

I took the endcap off the muffler and found a piece of pipe with holes in it inside the packing. One end is reduced down, kind of cone shaped, why I don't know. I've been toying with the idea of making a new baffle with caps on each end that would fit tight in between the front of the muffler, and the endcap. Of course the caps on each end would be open, and the pipe between them would be drilled in several places around it's circumfrence. Just removing the piece of screenwire/spark arrestor seems to have helped. You can feel the exhaust hitting your hand from 2' or more away from the muffler end, which I couldn't before.

I work nights so I was up late/early. I removed the intake and polished the inside. It's not like a mirror, and no engine builders are knocking at my door... but one heck of alot smoother than it was.

 

Man, Talk about scratching an itch! haha.

I know spark arrestors slow things down so it's good that sucker is out. Sounds like you really did a good job on the airflow! That's awsome. Maybe the review that talked about massive exhaust restriction was an anomoly. I'll let you know whats up when I get mine.

-JNY