Stalling the rain ...
 

I just got back from a ride in the rain and I once again had the problem of my '98 SHawk dying every 3 or 4 miles. This has happened pretty consistently since I've owned it, just about 10 years now. I solve the problem temporarily by stopping and opening the filler cap. Because this works (temporarily) I've thought that the problem had to do with gas tank venting - either something wrong with the hose (routing?) or the cap (allowing water somehow to clog the venting passage).

Anyway, has anyone else had this problem, and more importantly, has anyone solved this problem? I'd sure love to know what the solution is. Suggestions? Solutions? Troubleshooting procedure?

Thanks in advance

I know the answer
 

I had the same problem for years too. I thought it was the sidestand kill switch shorting in the rain, and even removed the switch, installed a "rainboot', and reinstalled it. On the way down to and back from the Indy MotoGP it happened again. I had a spare key and was opening the gas cap at speed and it would clear up. I finally stopped and pulled out the tank breather hose (the small one, not the bigger drain hose) and re-routed the breather hose (it was pinched), and poof, the problem went away. It is definately the tank breather hose. Re-route it (and possibly use a longer length of hose) so it has gentle, gradual downward bends and is not pinched or crimped and so it ends behind the chin fairing, and the issue will disappear.

Thanks, skokievtr. It's good to know that I'm not crazy. ;) I actually rerouted the vent tube years ago and I thought that that solved the problem, so having the problem again stumped me. I'll try rerouting it again.

While on the topic of stalling, have you, or anyone, experienced stalling after filling up? I thought that maybe this was due to overfilling, or somehow dripping some gas down the drain tube (but isn't that what it's for??), but I've never figured it out.

Ahh, the charming 'character' of the Super Hawk, eh? ;)

Soundsike vapor lock to me, especially with the problem you are already having.

Vapor lock is cylinder related, right? Or do you mean that water is preventing proper tank ventilation? The first problem happens in the rain only, the second problem happens occasionally when I fill up - maybe it's all related to the ventilation tube.

As I think about it now, the original owner had removed the charcoal canister and maybe he did a bad job routing the venting tube. Seems like there would be more people complaining about this problem it was happening to an unmodified bike.

I was refering to proper tank ventilation. I would definitely check the vent tube. I had a dirt dobber build a nest in the vent hose on one of our four wheelers and it would do the same thing. Check the routing and give it a squeeze to feel for hard spots indicating clogs.

Is yours a CA model 98, I did not think any 98s had a evap charcoal canister but I could be wrong. If so go here http://home.nycap.rr.com/ghlbo/index.html

Has the PAIR system been removed? Go here http://home.nycap.rr.com/ghlbo/index.html

The original gas tank vent line may have been re-routed but make sure it is now a single, longer clean line with as straight of routing as possible down to the chin fairing. If it was a CA model, make sure all the unused vacuum lines and ports are plugged and the PAIR system eliminated properly with no vacuum or intake leaks, and all unused ports in the air box are sealed or capped. There was a T in the vent or vacuum lines that had to be eliminated. I've never had the fill-up stalling problem but you need to re-route the carb vent lines as shown herehttp://home.nycap.rr.com/ghlbo/index.html

Thanks for all of the great tips, skokie. I plan to work on the motor this winter when I'll have the bike off of the NYC street. Dealing with the PAIR system has been itching me for some time, I've just been lazy about it.

Funny, I thought that if any state required the charcoal canister it would be CA.

CA was the only state... do u have any info on where it was originally titled?

A small but possibly usefull tip... cutting the end of the breather hose at an angle reduces the chance of surface tension holding water static at the end... Obviously looking at the routing and making sure there is no kinks is the first step though...