montynormand
Member
got this email from a buddy who purchased this sled over the summer. Sled has only 900 miles on it!! any ideas to help him out?
By the way, I cleaned the carbs on the VMAX over the weekend and was disappointed that it didn't help the sled run any better. I actually tore them down twice and there really wasn't much difference even though I cleaned out a bunch of crap out of the bowl and the jets. When I first start the sled, I am still getting lots of back-fires until the sled warms up. Once it is warm, then it runs fine, but it starts really hard. There seems to be good throttle response and what-not once it is warm. The sled also idles pretty low at only about 1000-1200 RPMs too, but that should be pretty easy to adjust once I feel as though it is running correctly. Go figure. I haven't played with the idle air screw or anything yet, but will perhaps see if I can adjust this out as my next step. I would assume that it should be set up correctly already, but maybe the guy that had it before me was messing with it. I just hate changing it if it was already tuned and the problem is elsewhere. I am not convinced that this is an idle jetting issue, since I was seeing backfiring even as I was reving the track at 40 MPH when it was still cold.
Also, I am still disappointed with the clutching on the VMAX. When I put it up on the stand, the clutch will engage at about 3800 to 4000 RPM and then will immediately start closing as speed increases. Even with the track spinning at 50 to 60 MPH, the RPMs never really get above 5500 to maybe 6000. I would assume it may be different if I am riding the sled and have weight against the belt, but I hope I will see higher RPMs in the power band of the motor.
By the way, I cleaned the carbs on the VMAX over the weekend and was disappointed that it didn't help the sled run any better. I actually tore them down twice and there really wasn't much difference even though I cleaned out a bunch of crap out of the bowl and the jets. When I first start the sled, I am still getting lots of back-fires until the sled warms up. Once it is warm, then it runs fine, but it starts really hard. There seems to be good throttle response and what-not once it is warm. The sled also idles pretty low at only about 1000-1200 RPMs too, but that should be pretty easy to adjust once I feel as though it is running correctly. Go figure. I haven't played with the idle air screw or anything yet, but will perhaps see if I can adjust this out as my next step. I would assume that it should be set up correctly already, but maybe the guy that had it before me was messing with it. I just hate changing it if it was already tuned and the problem is elsewhere. I am not convinced that this is an idle jetting issue, since I was seeing backfiring even as I was reving the track at 40 MPH when it was still cold.
Also, I am still disappointed with the clutching on the VMAX. When I put it up on the stand, the clutch will engage at about 3800 to 4000 RPM and then will immediately start closing as speed increases. Even with the track spinning at 50 to 60 MPH, the RPMs never really get above 5500 to maybe 6000. I would assume it may be different if I am riding the sled and have weight against the belt, but I hope I will see higher RPMs in the power band of the motor.
daman
New member
The B/F could be a lean condtion, did you check to see if all jets where cleaned very good(can see through them?) AND are the right size?
FuzzButt
New member
I had backfires till I replaced the fiber doughnut seal at the end of the Y-pipe.
Ya I agree with Daman take the carburetors apart again and check to make sure they are the right ones for your altitude. On the Tech pages there is the jetting guide. An at idle backfire would be pilots and should be the long type #45's I believe. Make sure the passages past the jet are also clean.
FWIW my 600 needs a bit of "Starter Time" to get it running when it is cold. Always has. If I had to pull start it I would be screwed.
Ya I agree with Daman take the carburetors apart again and check to make sure they are the right ones for your altitude. On the Tech pages there is the jetting guide. An at idle backfire would be pilots and should be the long type #45's I believe. Make sure the passages past the jet are also clean.
FWIW my 600 needs a bit of "Starter Time" to get it running when it is cold. Always has. If I had to pull start it I would be screwed.