So when I got my superhawk, it would lift the front in first, second, whatever. That's really the only metric I have to go by...

I let the bike sit for 8 months for various reasons, then it wouldn't start... so I took off the carbs out and cleaned them, found black debris in one of the jets, blew it out, fine. Reassembled the bike, charged the battery, and rode it around... blah.

I've been chasing down what went wrong ever since. When I put it back together, it had all the power of a ninja 250. I went through all the vacuum lines to figure what I screwed up, and decided to remove the CA and PAIR in the process. On this forum I learned about PVLIR... it rode better after fixing that.

A new sputtering problem started shortly after, which I narrowed down to a ripped petcock vacuum diaphragm. Fixed that, then synced the carbs, now it runs very smoothly, with approximately SV650 power.

I can tell it's running lean, I have a lingering tach needle on throttle cuts, better off idle with choke out a little, etc. I intend to work on the jetting, set the TPS, etc etc, but my question for anyone listening is-- why the hell doesn't it run at least as well as it did before I stored it? Does it sound like I still have a vacuum problem? It's gutless, it breaks my heart.

I plugged the two vacuum ports on the carb used for syncing, and the hole in the airbox. I flipped the PAIR reed valves, and capped the barbs. I left (4) vents open on the carbs, (2) per carb. Does this sound right? I'll get down in there with ether or something to check vacuum leaks around the airbox tomorrow. So frustrating.

I'm getting really fast at pulling the tank and airbox though...

 

There should be only one vent hose for each carb, the large one with a 90 degree bend that faces the opposite side of the bike when hanging loose. Make sure the ends of those 2 hoses don't point upwards. All other disconnected vacuum hoses should be plugged.

 

Under the vents you mentioned on each carb is another little elbow barb, and they have hose connecting each other in a T junction, with on end open to the air. I will plug that and see if there's a difference, although I couldn't feel any positive or negative pressure putting my finger over it, nor a change in idle. Will report back with results--


Also, I should mention that I bought a petcock repair kit from carbkitcapital for a GL1500 aspencade (91-95). The large diaphragm (the one that tears) fit fine, however the smaller plug element would not seal... it looked identical but the lip was not thick enough, and gas was leaking out of the vent. So... look out for that.

 

feels torquier with the T blocked off, still not hoisting the front though. Still have a little gas in the petcock vacuum line, what gives? it couldn't be coming from the carb, right? I'm going to buy a new cover set from honda and be done with that... can't recommend the goldwing rebuild kit.

 

well, when a shop that did my jet kit gave me back my bike it felts the same way, it pulled, but nowhere near as hard as it should....when i gave them the bike it was lean like crazy cuz of shorthened Yoshi's on stock jetting and it would still pull like mad. turns out the diaphragm in the fwd carb didnt seat properly so it was leaking the vacuum out, so the slide wouldnt move out of the way...so you can imagine how much can a cylinder breathe through that little tiny opening that the slider has on the bottom.

take the black plastic cap off and see if the edge of the diaphragm is sitting in there correctly.

first check actually is to try cranking the bike over and see if the sliders are jumping, which would indicate whether its sealing or not.

 

A better (and easier) way to tell is to just lift the slides and make sure you hear sucking sounds and they fall at a controlled rate when released. If one snaps back shut when released then that is the one that is torn, pinched, or not seated correctly.

 

What is PVLIR? Searched but couldn't find it.

 

It all goes back to this thread: https://www.superhawkforum.com/forum...ighlight=pvlir

Petcock Vacuum Line Inadvertent Relocation.

The vacuum hose to the petcock goes on the back of the petcock to the nipple pointing right.. The one on the bottom of the petcock that looks like it should have the vacuum line is actually the vent and is left open to the air.

 

Okay...

Been more many months since I touched the poor Superhawk: been very busy with work, getting my license back (different bike ahem) and mountain biking.

I came back on the forum to re-research my original problem, and found several posts in my own thread mere days after I last checked it! Thank you Hawkrider and Red_liner for the diagnosis tips-- my rear slide snaps back into place with no controlled sucking whatsoever.

I'm going to endeavor to fix it in the next few days. Thanks for the help. Here's a picture of the bike in Frazier Park (middle of nowhere, CA). That was a great ride loop from Los Angeles, btw, a 300 mi. day. Anyone interested I'll disclose the details...

 

No need for me..... I used to live in Frazier Park for a while....

 

sounds like someone set up a sync vacuum hose for the rear cylinder. pls trace that hose, post photos if you can and we can help. The hose that gets T'ed for the sync is attached to the rear cylinder and then to the petcock. If it is compromised, you will have behavior as if your petcock is damaged or not hooked up correctly.

the other possibility is that your bike was dePAIRED and the vacuum line for the PAIR valve under the airbox was not plugged as it should have been. I think that hose attaches to a T on the front carb.

A photo would help.

if your slide moves too freely - meaning no sucking noise, you most likely have a diaphram out of place or torn.

On a final note, I have both a Superhawk and Hawk. The Hawk is capable of giving the Superhawk a hard time, especially in the twisties.

 

granted, although a hawk is fairly removed from the torque of the superhawk.

I've diagnosed the problem, the vacuum diaphragm on the rear petcock wasn't seated properly. I chased all the other vacuum line gremlins out well before that.

Photos and report pending with reassembly--- 8541Hawk, we take the 33 up from LA and jump over on Lockwood Valley. My favorite road out there is Pine Canyon, that was fun!

 

+100

 

fixed! now she feels like a bottomless pit of torque! It was a pain in the @ss getting it started again... cleaned the floats out, drained and replaced the gas, etc. I'm going to make a new thread in an appropriate forum and share pics. Thanks for the help!

-Ian

 

good to hear - if you have not already adjusted the TPS, you may want to. That adjustment made my SH start MUCH easier. JB