Hey all,
I just got my '87 cane back on the road after rebuilding it from the ground up. I replaced the stock "supertrap" exhaust with a Delkevic "stubby" can. The new exhaust is a straight through design (very loud!) and has no baffle. Delkevic told me that I would not have to rejet (I have the stock jets right now).

The issue I'm having is that the bike seems to run out of fuel while cruising, like the float bowls are being emptied too fast. It will begin to stutter and misfire if I hold the rpms above 4500 for more than 20 seconds or so. If I open the throttle just a little more the bike will run great. It will take off like a bat out of hell at WOT. The problem only exists when the rpms are held at a constant level. The higher level the rpms are held, the more noticeable it is. I can bring her from a stop up to 100+mph without any issues, but as soon as I try to hold a constant speed, it just stutters and misfires until the rpms drop below 5000, at that point it will run great.

Is this because of the different exhaust? Or do I just need to yank the carbs and give them a good cleaning? Or maybe a mixture adjustment would do the trick (richen it)?

 

Is your bike naked? if it is it's possible you are getting too much air through the holes on the fame that go to your airbox.
And if not i would definitely suggest cleaning the carbs and possibly rejet.

 

Try some seafoam additive in the gas tank first. Run 2-3 tanks of treated gas through your beastie and see if that takes care of the issue.

After that may have to check into carb cleaning and then possibly a re-jet (in that order). That will give you the best chance of your work/money vs results.

Ern

 

Thanks guys. I stole the stock can of another cane to see if the exhaust was the problem. It made no difference, the bike still runs crappy at highway speeds.

TWOFERJUAN, yes my bike is naked so it makes sense that too much air is being forced into the airbox. I'll stuff some rags in the frame to see if that makes any difference.

MadHattr059, seafoam was the first thing I did. Hasn't helped yet but I'm only on the first tank.

 

then im most definitely willing to bet thats the problem, as it was also my problem when i got my bike.

 

Yup, that's the problem! I took her on the highway last night at about 75mph and as soon as I placed my hand over one of the air intake holes she smoothed right out.

TWOFERJUAN, how did you go about fixing that issue? When I block the holes off completely the bike runs too rich and bogs down. Any tips?

 

I blocked the holes from the inside with duct tape, but recently with the change in weather ive been having problems again so i think i need to mess with my carbs again. but you can do a little duct tape tuning by not completely blocking off the whole inlet, that seemed to work the best for me.

 

Yeah I used duct tape last night when I went for a ride. It ran great but I'm looking for a more permanent solution. I tried taking the intake hoses off the air box but that just made the problem 10x worse.

 

yeah i havent really figured out anything "professional looking" yet. but if you figure something out let me know.