nath981

We're trying to get Steve29's (who started Disabled PAIR thread)bike sorted out and yesterday removed the carbs to remove air mix screws and slot them for easy adjustment. We also took carbs apart to ascertain jet sizes and needle settings. In the process of pulling the tops off the carbs, I was surprised that the caps did not push out when the screws were removed. The springs were different from OEM because when we reinstalled the caps, we just dropped the springs and put the cap on without the normal having to stuff the spring up the tube and carefully insert when putting the cap on. My question is, could this weak/short spring affect performance?

He doesn't know where or how these springs came to be other than they may have been part of the Dyno Jet Kit. Is this possible that they would include such a wimpy spring with their kit?

Sync question: when syncing with the quick sync set up (where you add the fitting and short length of tubing to the front carb and T into the rear carb/vacuum lin to the tank), do you disconnect the vacuum line and plug it or leave it in-line. It seems that to make sure that the sync is equalized, that the vacuum going from the tank to the rear carb should be separated from rear carbs so the you have equal lengths of tubing from each carb. The problem with plugging off the vacuum line going to the tank is that the engine shuts off after several minutes of idling. What is the proper method because i have done it both ways?

nath981

well steve29 got the answer for the carb spring question. Honda's killer spring is an unnecessary nuisance given that the Dynojet wimpy *** spring works better?

Still no answer on the carb sync questions.

SpellCheck

Maybe I'm overlooking something here, but I really can't see that it would make much of a difference by leaving the tank petcock connected or having slightly unequal length lines. Once the engine has run a moment and the rpm has settled down, the vacuum should be fairly constant (it pulses with the piston movement anyway, of course). And your sync tool doesn't show a perfectly steady reading either.

It's not like setting valve clearances, where you can fiddle a thousandth here or there till you get it right. You're going to have to settle for some approximation in the vacuum levels -- getting it "close enough." I think any differences caused by the line lengths or the petcock draw would fall within the jiggling of the readings anyway.

But I'll be the first to admit that I may be missing something.

Little_Horse

length of the hoses has no relevance and neither does the petcock hose staying connected. I always connect up to my t-fitting and leave the end connected to the petcock that way my gas stays on will sync. If you think about it the system is under negative pressure given enough time you could hook your bike up to a huge compressor tank and it would still read the same. If you are worried about it still you can take a pair of vice grips and a few deep sockets to make a poor mans hose clamp, then start the bike pinch the petcock vacuum line off and continue with the sync, but IMO thats extra work.

Little_Horse

oh and as far as the dyno jet spring is concerned they have you drill an extra hole in the slide to compensate for the shorter spring. So in the end it works basically same or at least in my experience no noticeable difference over, except for easier assembly.

SpellCheck

I agree with cornandp -- with the short springs and drilled slides, the carbs will work fine.

When I bought my '02 SH, it had Muzzy cans on it. The seller had no idea whether the carbs had been jetted. When I swapped back to the stock mufflers (got them with the bike) I took the carbs apart. Inside were the light springs, drilled slides and DJ needles.

I put it back together with stock jetting (per Greg's suggestion) and the DJ needles/drilled slides -- it runs fine through the rpm range, very rarely pops back through the exhaust, gets average gas mileage and has a decent idle. No complaints.

residentg

I love the dog, aren't they great.

nath981

Since we got steve29s bike running the best ever yesterday afternoon, so good he chose not to accept my offer to sync the carbs. Given that the bike is running perfectly, I am witness to the fact that the short light, spring works well.

My questions are valid , however spurred by a lack of understanding, not only about how each component works, but how everything functions together. When I look at the airbox, the carbs, velocity stacks, hoses, cables, wires,etc, I am humbled and even aghast at how Honda or anyone else could ever have figured all this mind boggling **** out, manufactured it to miniscule tolerances, and have it all work together. Now i certainly know that that this was a process of evolution over time, starting with relatively simple contraptions and slowly maturing into what we are riding today, but this still blows my mind and I have never taken it for granted, and this respect requires me work on them with the care of an artisan or physician,or maybe even a brain surgeon.

As I mentioned to Steve during our days of working on his bike, There's only a relatively few mechanics who really have a thorough understanding of how the whole vehicle, whether it be a truck, motorcycle or other, functions as a whole,that is how one system affects another, from the suspension, to engine components, to the electrical. I have been fortunate enough to work with one such person whom I assisted for 6 weeks in the process of modifying my tractor(84'Autoar I bought new and put 1.6 million miles on) to accept a large sleeper. These unique individuals are somehow able to so thoroughly understand not only how each system works internally, but also how they all work with each other. The majority of mechanics are more like me in that they become familiar through repitition and, even though very skilled through experience, can never achieve this level of insight. We lesser beings merely take things off and replace them, dismantle and rebuild, but cannot ever seem to reach Nirvana or enlightenment.

Thus my second question regarding the length of the vacuum lines, the one I cut going between the rear carb base and the petcock, and the added line from under the front carb. Given my lack of understanding described above, I was following what i read on this forum citing that the lines needed to be the same length which precipitated my question about how that would be affected by leaving the vacuum line hooked up to the tank(rear carb line would be long and front carb would be short). But you guys obviously understand what I don't. When I isolate and plug the line to the tank, and use only the two equal length tubes from the carb bases, the engine shuts off after a short period. My rational for this was that it was loading up or something similar and this was causing it to shut off, while what is really happening is that it is simply running out of fuel. Thanks for clearing up the fog on this and many other issues so that we unenlightened take off and replace mechanics don't have to totally rely on the trial and error method to keeps these Hawk running. Thanks, Nathan

happytrack44