My ski keeps shutting off on a hard side landing. Anytime I don't make a roll 100% plate to plate, even like 90% it shuts off like you pulled the lanyard. You can smell the fuel, and it takes a bit to get started and cleared out again. My theory is that the pop off could be to low causing the needle to open and flood the engine. After I burn it out for about 20 seconds it runs great. Here's how it started:
It's a 62t/61x 82mm fully ported engine that I haven't gotten tuned quite right since it was assembled mid summer. All the issues up until now have been identified and fixed to the point that I thought it was running about 75% of what it should a few rides back (none of the dying on impact mess.) At the time I had a Wamilton's flame arrestor on it, the carbon one with the small holes over the engine. I switched it out in favor of new ProK's for a little more air flow. After putting the ProK's on and getting it tuned in a little better I felt like it was rich on the bottom but ran much better than ever before. The first time I landed a roll wrong it just shut off.
Get home and pull the carbs, everything looks great, as they were rebuilt when I built the engine. I decided to build a pop off tester to verify what I had. Turns out I had 65g silver springs instead of 95g springs. I replaced the springs with 95g's and now my ghetto tester is consecutively giving me around 40psi on each carb. The ski once again ran MUCH better than ever before all around, but still has the side smash problem. At this point it's much easier to start and clear out after a hard side landed/shut off, and it it happens a lot less than before so I feel like I'm on the right track. Any ideas on why it changed so drastically with the change ProKs? I realize your flame arrestor directly affects pop-off but could it cause this?
Also for what it's worth I have since added a reed spacer, checked reeds (new vforce 2's at time of built) etc just to make sure there were no obvious problems.
Current specs:
75 pilot
135 main
1.5 N&S w/95g spring about 40psi
Vforce 2's
Case/cylinder porting
Bpipe w/ATP waterbox
Sorry for the novel, just want to cover it all. Next step will be to try stock 115g gold springs if I can round some up. Thanks!
It's a 62t/61x 82mm fully ported engine that I haven't gotten tuned quite right since it was assembled mid summer. All the issues up until now have been identified and fixed to the point that I thought it was running about 75% of what it should a few rides back (none of the dying on impact mess.) At the time I had a Wamilton's flame arrestor on it, the carbon one with the small holes over the engine. I switched it out in favor of new ProK's for a little more air flow. After putting the ProK's on and getting it tuned in a little better I felt like it was rich on the bottom but ran much better than ever before. The first time I landed a roll wrong it just shut off.
Get home and pull the carbs, everything looks great, as they were rebuilt when I built the engine. I decided to build a pop off tester to verify what I had. Turns out I had 65g silver springs instead of 95g springs. I replaced the springs with 95g's and now my ghetto tester is consecutively giving me around 40psi on each carb. The ski once again ran MUCH better than ever before all around, but still has the side smash problem. At this point it's much easier to start and clear out after a hard side landed/shut off, and it it happens a lot less than before so I feel like I'm on the right track. Any ideas on why it changed so drastically with the change ProKs? I realize your flame arrestor directly affects pop-off but could it cause this?
Also for what it's worth I have since added a reed spacer, checked reeds (new vforce 2's at time of built) etc just to make sure there were no obvious problems.
Current specs:
75 pilot
135 main
1.5 N&S w/95g spring about 40psi
Vforce 2's
Case/cylinder porting
Bpipe w/ATP waterbox
Sorry for the novel, just want to cover it all. Next step will be to try stock 115g gold springs if I can round some up. Thanks!
