LightningTeg
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Hey guys
Recently I changed my stage 1 predator 420 from a straight through tractor muffler to a straight through bike muffler with fiberglass packing to get the volume down. Really I didn't think there was much difference as far as restriction goes.
But it must be the case that its a bit more restrictive because I cant get the thing to start now. I was able too the first day after I put the new muffler on after taking the spark plug out and cleaning it off. It was black, so it was definitely running rich before too, but also wet. I cleaned it off with brake cleaner and hit it with a wire wheel and let the cylinder air out and got it running. The next day it just wouldn't start.
Unrelated but stock this motor required the choke to be on to start, even after hot lapping it. After putting the stage 1 kit on, after the engine is started, if you dont leave the choke on and take off with it and turn choke off mid acceleration the engine just turns off until the engine is warmed up. When I stepped on the gas sometimes it would just die unless you jab it even warmed up. Seems like this problem got better with the slightly more restrictive muffler. Either way, its super annoying having to manipulate the choke constantly at low speeds and starting. I have a little lever I rigged up to reach the driver so its not a show stopper but I shouldnt have to.
I think I know the problem is I need to put a slightly smaller jet in but what size should I start with? I dont know what size the stock one is. I think the one in there now is a 0.042? I was going to get some micro drill bits and open up the stock one
Recently I changed my stage 1 predator 420 from a straight through tractor muffler to a straight through bike muffler with fiberglass packing to get the volume down. Really I didn't think there was much difference as far as restriction goes.
But it must be the case that its a bit more restrictive because I cant get the thing to start now. I was able too the first day after I put the new muffler on after taking the spark plug out and cleaning it off. It was black, so it was definitely running rich before too, but also wet. I cleaned it off with brake cleaner and hit it with a wire wheel and let the cylinder air out and got it running. The next day it just wouldn't start.
Unrelated but stock this motor required the choke to be on to start, even after hot lapping it. After putting the stage 1 kit on, after the engine is started, if you dont leave the choke on and take off with it and turn choke off mid acceleration the engine just turns off until the engine is warmed up. When I stepped on the gas sometimes it would just die unless you jab it even warmed up. Seems like this problem got better with the slightly more restrictive muffler. Either way, its super annoying having to manipulate the choke constantly at low speeds and starting. I have a little lever I rigged up to reach the driver so its not a show stopper but I shouldnt have to.
I think I know the problem is I need to put a slightly smaller jet in but what size should I start with? I dont know what size the stock one is. I think the one in there now is a 0.042? I was going to get some micro drill bits and open up the stock one
