Dan7305 Posted October 20, 2016 Report Share Posted October 20, 2016 Ok, I posted this in the jetting forum, but I no longer think it's jetting. I really am not sure at this point. https://youtu.be/SyopnBw_NHw?t=14s You can hear in the video at 17-18 seconds when I go from barely on the throttle to wide open throttle. Given that I am holding it wide open, the only thing jetting wise that should have an affect is the size of the main jet, unless I'm wrong on that. I bought the machine needing a re-build, so I rebuilt it with a F.A.S.T. trued/welded stock stroke crank. I had Herr Jugs do a port job, and bore the cylinders to start fresh and clean. I picked up a ricky stator DC conversion, which caused issues similar to this, but way worse. I put the stock stator back on, with a floated ground, and it got better, but is still struggling to get to the power band. I also have an adjustable timing plate set at about 3 degrees advanced. I did a leak down test, and I went from 6 psi to 3 psi in about 50 minutes. Not perfect, but I don't think that's nearly enough to cause my issue. Should I just start throwing parts at it? It has a Dynatek coil on it, which shows .5 ohms on the primary with 10k on the secondary, book says 7k, should I start there? My stator Ohms out great. Anyone in the northern suburbs of the twin cities interested in letting me try a known good coil? Quote Link to comment Share on other sites More sharing options...
Surfrjag Posted October 20, 2016 Report Share Posted October 20, 2016 Is stator and cdi oem? Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 20, 2016 Author Report Share Posted October 20, 2016 Stator is OEM, coil is Dynatek. I was understanding that even at lower RPM, at WOT, the clip and needle only have so much to do with anything. Either way, while in the sad I moved the clip from position 2 to 4, or 4 to 2, whichever, leaning it out, and there was no difference in the way it ran. Tors is deleted. I do have a cool head, 22cc domes as that's what came with it. No I haven't checked the squish, I'll look into how to do that. Carbs are synced. Last I checked, before break in, both cylinders were at 120 psi. Air filters are clean, I haven't CHECKED the ground, but I did have the motor out, never painted anything, and it was all clean when it went back together. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted October 21, 2016 Report Share Posted October 21, 2016 What gap are your plugs at Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 21, 2016 Author Report Share Posted October 21, 2016 I checked plug gap before hitting the road this morning, was around .031, I'll pick up some solder to do the squish test hopefully Saturday night. Quote Link to comment Share on other sites More sharing options...
ginger Posted October 21, 2016 Report Share Posted October 21, 2016 i always gap mine at .02 idk why, i guess thats because thats what i used to gap my 250's at. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted October 22, 2016 Report Share Posted October 22, 2016 .018-.020 Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 23, 2016 Author Report Share Posted October 23, 2016 Just did the squish with solder through the plug holes, I got .050 to .052, taking multiple tests. Compression is 125 psi in both cylinders. Think it could be just the plug gap? Seems simple enough to work... Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted October 24, 2016 Report Share Posted October 24, 2016 I've seen stranger things happen, I would like to see the gap closed and find a coil that gives you 4-7.5 kohm cap to cap Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted October 24, 2016 Report Share Posted October 24, 2016 You also said you did lose a little pressure on the leakdown I would like for you to soap the intakes and check the crank seals. I know it was minimal but if it's a crank seal leak will get worse once cranks spinning Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 24, 2016 Author Report Share Posted October 24, 2016 Brought the plug gap down to about .022. My gapper only goes to .020, I could try smaller, but I don't notice a difference after adjusting the gap. I'm going to double check that I moved the running the correct direction, and that I didn't retard it 3 degrees. While in there I'll check that side crank seal. Any problem tipping it on the left side to not have to drain the oil to check the output side of the crank? I've coated everything visible outside the motor with soapy water before during a leak down. My plug wires have about 5,000 ohms each also, but that looks normal according to a Google. So I could find were automotive sources though. I'm getting tempted to just send the $60+ your way for a new coil... I'd almost be worth it before ripping the motor down again. Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted October 24, 2016 Report Share Posted October 24, 2016 I didn't watch the video. Stock stator with "floated ground"...... are you 100% sure this was done correctly? Dyna coil....... are you 100% sure it's good? No tors? No e-brake shit? Crossover tube installed? Float bowls on correct side? Good ground? These things are very simple. I'd be amazed if one of the above isn't the culprit. Sent from my SAMSUNG-SM-G891A using Tapatalk Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 24, 2016 Author Report Share Posted October 24, 2016 I'm fairly certain I floated the ground correctly. The dc regulator is functioning still, I rode for a solid 4 hours at night running lights. So I'd say that's a good sign. Dyna coil is suspect with 10k ohms on the secondary coil. Tors is gone, aftermarket mikuni cable and caps, no leak at the caps. E-brake is gone, lever and switch are there, zip tied closed. Crossover and float bowls are correct. Grounds should be good, I didn't paint the motor or anything, and the mounts were clean metal I both sides. I'm leaning towards the coil. Quote Link to comment Share on other sites More sharing options...
hoppedupandcutdown Posted October 25, 2016 Report Share Posted October 25, 2016 I knew a guy that had a rodent put some some nuts in his pipes while he had his engine rebuilt. I took about 3/4 throttle to lift them and plug the pipe Quote Link to comment Share on other sites More sharing options...
Dan7305 Posted October 25, 2016 Author Report Share Posted October 25, 2016 If the pipes were plugged, I wouldn't expect the power band to come on at all. Fixing a crank seal is pulling the motor apart again, right? I have a trip to glamis planned in January, and I'm running out of time here in Minnesota to get a test ride in before it gets really cold. Because of that, with my luck, I'd fix it, take it to California without a test ride, and have something go wrong out there. I think I'll leave the leak till after that and then tackle it. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.