I have a 98 Superhawk (just got it) that is stock other than a set of Scorpion slip ons. My problem begins once the engine is warmed up. It will idle smooth at 1100rpm and just stop. It does not slow or make any noises, it just shuts off with in a minute or two. There are no other problems with the way it runs but, its just very annoying to have it cut off while at a stoplight in traffic. I have it at the dealership now to have the jetting checked and a general check over and the Tech says the bike runs perfect and does not seem to need jetting. Anyone have any other ideas?

 

hey there alterego...

when i bought my 2000 vtr, one of the first things i did was install d&d slip ons and a k&n air filter. the thing was soooo lean, that it was basically stalling just sitting there...like yours.
now, i know that these bikes (as do all) run and are jetted lean from the factory. works pretty well with stock stuff. but start altering and adding more flow, especially air and exhaust, and you have what you have.

try getting and installing a stage 1 jet kit and at the same time have the carburetors synched. the jet kit (air filter, exhaust slip ons or neither), will wake that bike up and make it run the way it is meant to run. you WILL NOT regret it.

sounds like your hawk is running leaner with those slip ons and causing your issue. again, stage 1 kit and synching those carbs will wake that monster up.

let me know when you get it done and how it feels.

 

That's partly good advice.

K&N filters are problematic for the hawk, as are the dynojet kits. I'd stay with the OEM air filter and read the Carb set up thread and use those settings.

If it idles decently at 1100 it shouldn't stall out just from being lean. Could need just a sync, but check all vacuum hoses and Carb boots also

 

+1 on what AJA said, also check your TPS should be 500 or less and will help with your problem.

All of this information is readily available in the Knowledge Base.

 

I just experienced similar symptoms and I ended up rebuilding the petcock. The diaphram was bad and wouldn't flow all the time causing a lean condition at idle. I haven't had it stall since.

 

Thanks for everyone's help. I'll check this stuff over and let you know what I figure out.

 

I found a new set of spark plugs in mine did wonders. They were covered in black jive from being to rich for years now that im leaned out, a nice brown film has formed proving my tune is good. Prior I had blippy issues at idle but not anymore!

 

That's the one..... check the TPS and also I would check the plugs while you were at it like was also posted....

 

Got it back from the shop and the mechanic said it was one of best running hawks he has seen. But, while riding home it did stall while at idle sitting at a red light. Plugs are good idle is set correctly and they said everything is good with the carbs.

 

Balance the carbs and if it persists raise the idle a notch to 1200.

 

Did you adjust the TPS yet?

 

Spot on. Roger told me that is where the idle should be for the SH.

 

Got to do a search on how to do that but it's next on the list of things to try.

 

Dang the TPS adjustment sounds a little intimidating.

 

Have you taken the carbs off ever? And do you have a dremel and multimeter?

 

No have not taken them off before. I don't a dremel and only a shitty multimeter. I may just have to pick some up and take a crack at it and see how it goes.

 

You can get a decent digital multimeter at Sear, Lowes,Home Depot and many others for $20.00 or less. If you remove the pair system it can be done without even pulling the carbs and you get to throw the pair system away at the same time

 

Please don't take this the wrong way and it may not even be the case. It sounds like you don't have much mechanical savvy, so you need to determine whether you want to start messing with internals because you can screw **** up fast and essentially multiply your problems not to mention needless monetary expenses. I've seen it happen.

If you can find a friend who has experience wrenching, it might be prudent to ask for help. Otherwise, there may be other Hawk owners around Richmond who would be willing to lend a hand.

If you do decide to tackle this, as you can see, there are helpful hands on board, just take it slow and easy.

 

I had the same problem. remove the rear cylinder vaccume line at the cylinder. Leave the other end attached to the fuel valve petcock under the rear of the tank. Apply suction to the line and see if it holds vaccume. If it leaks pressure - the fuel valve petcock needs to be rebuilt. If the diaphram has a hole in it, the fuel is being shut off from the tank to the carbs resulting in low idle stalls and a rough idle.

 

Thanks for everyone's help my Hawk is running top notch now!! New spark plugs, set TPS and away it goes.