jswisc

05 with 23k. Bike died a few weeks ago while doing 70 on the freeway. Just stopped running abruptly. Didn't have the time to look at it myself so took it to the Honda store. Mechanic had a superhawk himself. He found no spark so they narrowed it down to a bad spark capacitor, the second computer. I took the bike back and replaced the item myself. Started right up but rear cylinder is not firing. I checked spark, nice and bright blue with new plug. Compression is 150. Seems there is no gas making to the chamber. Any ideas what could have been put back together incorrectly that would lead to no fuel just to the rear carb?

CrankenFine

Confirm the no fuel condition by opening the float bowl drain screw first on the carb you suspect. You can slip a small size clear tubing on the nipple below the screw to prevent gas spill on the coolant res. area. Go from there.

Maybe spark time occurrence to rear cylinder is what's changed now. In my experience it would be an odd coincidence to have a fuel and electrical problem occur simultaneously.

jswisc

I agree. The only variable is what was disconnected by the Honda shop while they were troubleshooting. After installing the cdi box it started normal but then I noticed a stumble as I blipped the throttle. As it warmed it wouldn't idle on it's own without my help. I felt the rear pipe and it was cold. I expected a wet plug after running for 2 minutes or so but it was nice and lite brown. I will check the rear carb for fuel.

jswisc

When I had the initial loss of power I was cruising at about 70. While coasting to a stop I tried bump starting the bike. Is it possible, with a slack cam chain, to jump a few teeth on the sprocket? Valves must be ok because compression is 150 psi. Can a few teeth off prevent the cylinder from firing?

CruxGNZ

Why would you say that your cam chain is slack?

If I remember right, the cams can jump two teeth before interference occurs. The engine should still run however.

If ya ever need a hand with anything, you are only a half hour South West of me. I'm always down for a ride.

EDIT: FYI, the left side muffler will warm up quicker than the right. It has to do with the design of the header.

CrankenFine

Only if you had CCT failure at that moment since that is precisely what they prevent. So if that chain moved several teeth you'd reasonably expect to see compression to be negatively impacted if not valves as well. From my point of view bump starting is no different from hitting your starter in terms of strain on timing chains.

jswisc

Problem solved. I felt it was a fuel issue so that led me to the tank. Turns out the vacuum line was hooked up to the wrong fitting, the one on the bottum. Swtiched to the horizontal one and she started up and ran fine. The dealer ( not gonna flame), had his mechanic who owned a hawk work on the bike. He diagnosed the cdi box by swapping parts off his bike. Very nice of them and saved me a ton. I decided to take the bike back and finish myself (cdi from them, $506, partzilla $331). He must have put the vacuum hose on by mistake. I will pm you cruxgnz. Always looking for another Hawk. I ride with a group most Sat am. Fast paced ride out to New Glarus for breakfast at the hotel there and then twisties from there to the Missisippi for a couple of hrs. Usually home by 1.

CrankenFine

Glad it sorted so easily for you. Happy trails.

CruxGNZ

Another victim of PVLIR haha