Hawk won't run
 

Last night I cleaned and oiled the K&N air filter and took off the slip ons. Took them inside and polished them up all nice and shiny. Now I think I have a serious lack of back pressure issue after putting them back on. It appears exhaust is leaking out the front of the cans where they connect to the exhaust pipes. Mounted them the same and the springs are back on but can't get it to seal. Will only run with choke and throttle and horribly rough, shaking the whole bike. My guess is I am going to need to get some kind of sealant to go on the exhaust pipe before putting the cans back on.

Am I heading in the right direction? Is there some thing I am missing? Thanks for the help ahead of time!!

High temp gasket sealant is a good idea.

Did you over-oil the K&N? Might be part of the issue.

I might have, what would be ideal for dealing with that? Wash it again and oil it lighter?

Also, what was weird, one of the cans when I was looking into it there was this long wire mesh tube that looked like it should be lined up and one end is now dropped down so it is not inline any more. Broken baffle retainer maybe? I will use some of the sealant to try to lock that end back in place as well.

If the retainer is falling down, you may need new packing as well.

Runs only with choke? Is your petcock hooked up properly? (vacuum hose should be attached to the BACK not the bottom). These bikes will idle decently with no cans attached, so I'm guessing you have another issue brewing...

There are tabs on the inside of the end caps that hold the core in place on Two Bros. pipes. The core had cut thru them on mine also,letting it fall to the bottom of the canister. I know a welder who repaired them,I also repacked them while they were apart. Two Bros. sells a repack kit (you will need 2) that comes with new SS rivets and the drill bit to drill out the old ones.

In addition to the K+N filter, there are two triangular rubber or neoprene covers that have to be installed properly in the air box before your bike will run properly. I'd check that before doing anything more with the slip-ons.

First of all, Matt365, right on with the filter. It was over oiled. I pulled the air filter out and there was a pool of oil in one of the corners and you could see filter oil on the slides. I pulled out the whole air box, cleaned out all the excess oil, wiped down the filter again to make sure I had any excess oil, cleaned the slides, etc. While I had the air box off I took a look at the carbs.

It appears the PAIR removal was done, there is a metal tube where the PAIR valve was and the air box hole is sealed. However, on the two tubes that are supposed to be capped there is nothing on them. What issues does this cause?

There are also two 1/8" brass tubes that curve out of and away from the carbs, less than an inch long and there is nothing on these. Do these need tubes or caps or anything? I also could not locate the vacuum locations to get tubes on to prepare for syncing.

Finally, since putting everything back together, the bike is running, it idles great but.. When you go to accelerate and get to about 4500 to 5000 RPM it starts cutting out like it is either starving for gas or getting too much air. I am pretty sure I got all the tubes and vents back on and it was at least in the same shape as when this all started, which it was running pretty awesome. Any further help would be greatly appreciated.

Fun to be getting my hands dirty but frustrating as well. Thanks all.

"I also could not locate the vacuum locations to get tubes on to prepare for syncing."

Hey pal, type the words "carb sync" in the search box and you'll have a ton of info. HAWKRIDER has a go-by on his website with photos and I'm sure a lot of the search results will have photos, also.

You will utilize the vac line that goes to the back of your fuel tank petcock for one of the lines. A lot of folks, myself included, cut that line, put a "T" in it and attach a piece of vacuum line that is used for synching and then plug it when not in use...that way you leave your petcock hooked up to your tank and only have to unplug the extra line you attached to your "t" when you sync your carbs.

You will need a fitting for the line from the front. A fitting from Honda runs about $4, part #16214-MB0-000, but you'll prob have to order it from your closest shop. The fitting replaces a 4mm allen head bolt that you can see from the right side of the front cylinder down to the right of the front carb boot. It doesn't really stand out, but it's there. (There are pics of this on HAWKRIDER's website and probably in about a dozen posts on this forum) After you install the fitting, attach a piece of vac line to that, leave it attached and just plug it when not in use.

Here is a link to one of the many, many threads that might help: https://www.superhawkforum.com/forum...fitting-21953/

Look at post #26 in the following thread for a pic of the fitting you need: https://www.superhawkforum.com/forum...-tuning-22213/

Again, utilize the search function and you'll have a ton of info. I'll let others chime in on your other issues. Hope this helps and good luck!

Which 2 tubes are you talking about and what diameter are they? I would bet they are the float bowl vents and need to be open.

As for the bike cutting out... PVLIR.... check the vacuum line to the petcock.... remove it from the fitting pointing down and put it on the fitting pointing to the side.... ;)

Well, this continues to go from bad to worse. I tore it down again, found the breather lines for the carbs were missing so got new vent tubes and fixed that. Capped off the little lead of the black adapter that was shown in the PAIR removal posting to cap. Put in the adapter on the front carb vacuum line, ran line and capped, put in a T adapter on the vent tube going to the gas tank and ran a new line over with the other one and capped it. Flipped the reed controller over to keep the reed closed on both cylinders. Put it all back together, washed out the air filter and sprayed a real light coating of oil. Made sure the vacuum line was on the right piece on the petcock and took it out for a ride.

Arrrrgghgghghhh, now it starts cutting out around 3K and sputtering, complete loss of power by 4K and it is back firing now. 4 hours in the sun and worse then it was before. Any other suggestions before I tear it down again?


And is it just me or is that hose that goes to the bottom left front of the air box absolutely ridiculous to put back on? That took the most time.. and removing/putting the gas tank...

This must be the evap purge ports. These tubes are only installed on California emissions equipped bikes. Their function is for purging the charcoal canister. If your bike does not have a evap canister then these fittings need to be plugged. If not, you will have a substantial vacuum leak.

For that airbox hose I used a set of long needle nose pliers pinching the clip open and a long rod to push the hose into position from underneath. It's a bitch.

I'm sure it is, but is the petcock in the full on position? Also check the fuel lines and any filters.

My suggestion would be to remove the K&N and toss it in the trash, install stock filter and proceed. You now removed the biggest variable and cause of more headaches than they're worth on SH's.

Thanks for the great ideas all. I tore it back down and found that I had capped off the vacuum air cut off valve on the side of the carb and not the piece regarding the PAIR system. So I put the original short hoses back in. Cleaned the air filter and "lightly" oiled it this time and re-assembled. My back is pretty bad so I ended up sitting in a chair to do the work and found it a lot easier to get the hose on.

Now it is running decent, in 1st and 2nd have good power up to red line. When I get to third and hit about 7K it cuts out like it is starving for fuel. I am going to take a look at the fuel lines and take the petcock and fuel filter out of the tank to see if moving the tank all around caused some issues with debris in the filter.

The cool thing is I was able to finish up the PAIR removal and get the new vacuum lines setup for doing the carb sync. Also there are now actual hoses for the breather tubes. Still some work to do but in much better shape. Should have left the exhaust canisters on the bike and dirty and just left the air filter alone. Gee whiz..

Check your petcock diaphragm while you are at it

Sounds like you are really getting to know the bike. It seems like you are making more variables than you can keep track of. I find its best to change one thing at a time to avoid this confusion. No way can anyone diagnose this long distance cuz so much has been changed.

It really sounds like the first issue you had was putting the vacuum hose on the decoy nipple on the petcock (nothing to do with pipes)

I really am getting to know it well! I did some more troubleshooting and test riding last night. What seems to be the issue is when I whack open the throttle to 3/4 to quickly it cuts out. Don't know if it is air or fuel begin the issue. I have an appointment to get the carb synch done on Thursday at a local shop so I will pass the rest of this on to them at that point. Thank you all for your help.

The real issue was stupidly over oiling the air filter and thinking it was the slip ons being the issue. My stupid genes were kicking in. Such a n00b... I actually took the AMI Honda course back in 1992 but only wrenched for a year. After that I started working on computers and haven't really done my own wrenching almost 19 years. If you don't use it, you loose it.

What did you do with those 2 short curved brass tubes?

I am surprised to hear that you plan on taking the bike to a shop for the synch process.

Yeah if you did all that stuff a carb sync will be a cakewalk. I gotta say I dont think its the issue and will add another variable.

Have you thought of fouled plugs due to all the oil? Have you disassembled and cleaned the carbs? Are all the air leaks from the box fixed? (all tubes plugged or connected? These seem more likely to be the issue as a big trottle opening would reveal a leak and cause stumble.

How did the bike run before all this mayem?

I say again ditch the K&N, it's probably still over oiled and it's still a tuning variable that causes more trouble than it's worth on these bikes, not all bikes but these bikes.

As you have Ca carbs on the bike, there are actually 3 fittings that need to be plugged. The 2 curved fitting (one on each carb) that are located under the float bowl vents and a straight fitting that is located by the idle speed adjuster.

If you had the carbs completely out, also check that they are fully seated in the isolators and that the clamping screws are tight.

I also agree that you would be better off with a stock air filter. ;)

A question... You said that you flipped the PAIR reed valves over... If the previous tinkerer that did the PAIR removal left the two connections to the PAIR open and uncapped, he likely had the reeds flipped so they stayed shut... IE, if you flipped them over again, you put them back, and now they are drawing air...

So open it up, look at the reed and see which way it operates... THEN put it back in backwards, so that it can't open...

Report back with findings...

:iagree: per the stock filter...

I will be getting a stock filter, although I don't know what this is going to do with all the jetting I had done last year.. I have not finished building the synch tool yet, have the parts for the manometer but not the carb adjustment tool yet. Still have to try to get the two cycle oil into that tiny hose.. I don't know if I can suck that much on a tiny tube... we will see. If I can't I sure won't be sharing that fact with anyone.. ;-)

I can go back and plug the two curved brass tubes as they are still open. And will check the other fitting as well. I actually did not flip the PAIR reeds over, per say, I flipped the little curved arm upside down so it is holding the reed shut from opening.

I did not take the carbs all the way off the bike and did not clean them or check the plugs. I can certainly check the plugs but not super excited about having to pull the carbs all the way out. Will cross that road if I need to. Like I said, it seems to run great until I whack it open to 3/4-WFO then there is hesitation and it clears up. If I accelerate smoothly without the aggressive twist it is ok.

FYI, I have the K&N filter and my bike runs and pulls perfectly. I want the stocker but cant bring myself to pay for another filter.