| Author | Message | ||
     Daemon512 |
After replacing the base gasket on my cylinder because of a leak, the bike ran perfectly fine, except for a new major leak out of the lower pushrod cover gasket, probably because I had tightened it too much. After letting it sit for a few weeks at a friend's place, I replaced that, and now there doesn't seem to be a leak, however... The bike starts up fine and begins going down the road with no problems, but a couple hundred feet down it begins to lose power and starts backfiring. I can usually keep it running, but it won't go much faster than 10MPH. I brought it back and put it in neutral, thought that maybe there was some carbon buildup that needed to be worked out, and revved the engine up high. If I can get it to rev, it seems to be able to stay at the high RPM's, though it will backfire often. However, it didn't help the problem at all. When I opened up the airbox to look, it seems as though the carburetor slides just fine, but when the engine is backfiring, fuel is spitting out of it. Looking around, I've tried a few of the things I've seen on the forum to fix the problem: -The spark plug is fairly new and sparks fine -I disabled the kick stand safety switch -When I block the carb intake with my hand I feel some suction, and the engine instantly loses power/stalls. -The fuel tank does not have a vacuum issue My boot looks fairly new, but I suppose it might still be that? Is there anything else I should check/other issues it could be? My only other thought is that the fuel tank is now pretty low, and that water may have condensed in it while it sat. I'm probably going to try new fuel next, if that might be part of the problem. I've read about an EPA box mod, but haven't been able to find any pictures that allow me to understand what exactly I'm supposed to be moving hoses around on. | ||
| Flatheadbill |
Did you get the pushrods reversed? | ||
| Daemon512 |
Looking at the manual, I thought I had them correct, the shorter one to the rear and the longer to the front (which I understood to be correct), but there's a chance I got them mixed up/put them in wrong. If I have time tomorrow I'll swap them and see if that solves it. | ||
| Gearheaderiko |
Flathead bill had a very good suggestion as it didn't seem to run right after the repair and given hydrolic lifters and your problem, definitely seems right on (at this point). Avoid trying to fix things with a modification, such as an air box modification. Bypassing the kickstand switch is reasonable as that isn't a running mod, just a safety switch bypass. Also avoid trying the shotgun approach of fixing everything. Wait and diagnose the problem. "Fixing everything" will just waste money, cause frustration and potentially lead to more problems. Coincidences do happen though, so it could be something unrelated to your repair, but start there first. Keep us posted. | ||
| Gearheaderiko |
If you go to TDC (compression stroke) one will feel real tight, the spin quite freely. Check it before you remove the pushrods and after you switch them out. Remember, with hydrolic pushrods, they may or may not bleed down or pump back up consistently or just when you want them too! | ||
| Daemon512 |
Thanks for the advice Gearheader. The biggest reason I tried those things first was that I don't have another mode of transportation without borrowing a vehicle, and its a decent trip to the nearest place to buy parts. Something I could do at home with existing tools was more appealing. It very well might be that this is my issue, thinking back I don't think I moved things to TDC to disassemble/reassemble. I hope I didn't cause more permanent damage as a result. Hopefully I'll get over to check it out this weekend (work permitting) and I'll let you know how it goes. I'll try the rods first and then go to get das boot. | ||
| Daemon512 |
Well, I took it apart and swapped the pushrods, checking them when I did. It looked like I had them right to begin with, but I assembled it to check anyway, and it didn't seem to have any change. I swapped them back to the way it looked to me like they should be in the manual (the original way I had it). My next guess is the boot. Some more background that I've found, the gas tank had a crack in it and was leaking fuel. The fuel caused the rubber "stud" that holds the tank in place on that side to crack and fall apart. Since that's the same side as the boot, I'm wondering if it did the same to the boot. It'll come off and be inspected later tonight, and I'll go get one tomorrow morning when I can. Does anyone have any other ideas? When I took the bike apart to fix the latest oil leak, I didn't just remove the boot, I took the angle of tubing off the motor as well. Could I have done something to that to cause the issue? | ||
| Gearheaderiko |
Yes. The O-ring can become delicate with age and it's easy to over torque the manifold. | ||
| Daemon512 |
I think the manifold was the problem. I took it off and inspected the boot, the boot seems perfectly fine. I cleaned the manifold, o-ring, and where it attached, and put it on without torquing the bolts down heinously tight. Its seeming to run fine now, just have to await the test ride. Thank you! |
