When I last left you, I was solving the problem with loss of power, and backfiring through the carb when the lights were on. That was solved: ignition switch caused all the problems. I still have no issues after changing out the ignition switch.

The hesitation/stutter/jerky remained however at low RPM (below 3000). I put in baffles (my drag pipes flare out to 2.5” at the end of the pipes) to see if that would solve the problem. THAT solved or lessened the stutter/jerky low rpm problem. BUT I could hear it was there even if lessened. Also, occasionally the carb would sneeze on a slow roll acceleration. On a slow roll acceleration, the bike flattened out and then…caught up. I figured this was a pilot jet issue with the baffle combination. So, the baffles caused the low rpm slow roll acceleration hesitation with a occasional carb sneeze.

Then I watched this:


My drag pipes are far larger than in the S&S example—S&S drags look 1 7/16 or so. As I wrote above, mine flare out to 2.5. So, then, when S&S baffled them, it went from small to really small. When I put in my baffles it was similar to a slip on in size, but, I lost a lot of power in the low-mid range, but the bike performed as expected under rapid acceleration. I may end up pulling the baffles and trying them unwrapped/less wrapped, or remove them completely. I love the sound without them. A further problem I have with the video is that mufflers are wrapped baffles, so….it seems that in his example—small drag pipe opening—is not applicable to my situation. But, he is right about everything he presented in terms of performance.

In the meantime, I decided to rebuild the carb. Two problems presented themselves immediately.

1. no gasket on the backing pate. I mean none! This would mess up the S&S intake meethinks. I also think the spacer was shot. The surface of the intake manifold to spacer was….not clean to put it mildly. I am not sure I ever had a good seal there.
2. The jets: main jet was .74, but the intermediate jet was .262 (small!)

I bet the previous owner leaned out the pilot as S&S tried in the video with successful results. Under a high rpm situation, it helps. But, it is not suited for normal knock around town riding. The pilot jet is no doubt the cause (or a contributor) of the stutter/hesitation I think. I have ordered a main of .72 as per spec and went up to spec size .295 for the pilot.

It will be a couple days before I update this. Carb is going into a Berryman chem bath and must wait for new jets.

 

This is a real good video I've watched it before, but dyno tuning and riding tuning can be two different things, In my experience with drag pipes for riding the larger the diameter drag pipe the worse they perform, and I don't know what kind of baffles your using but some aftermarket ones are real junk restrictive, Me Id just get some good quality baffled pipes and tune the bike for them and drop those large diameter drag pipes

 

...you are right about the restriction on small drag pipes. Mine are about 1 ˝+ for he first few feet, then flare out to 2 ˝ in the last 12-16 inches at the end. Mine are different than the S&S baffle experiment because theirs was around 1 7/8 and then they baffled. Mine baffled remain approx. the same all the way through now--and they are V-twin baffs if I recall.

 

Your pipes sound like the old set I have on mine, mine have baffles put their not the best, pretty loud so the baffles in mine are not doing alot, I did put lollipops in the end of mine from DK customs. They did work pretty well and gave the pipes a more performance sound.

https://deadbeatcustoms.com/dk-custo...EaAuKgEALw_wcB

 

I fully appreciate you are trying to fix this issue yourself, and I applaud your efforts.

But, a good wrench with a Dyno could get you sorted out in a couple of hours and the bike will run the best it ever has, of course he will bitch about your pipes first.

I have been messing with carbs for years, yes you can get them real close. But nothing like a good Dyno to get her dialed in right.

Costs some $$$, but I have never been disappointed. Good luck.

 

!

....those are quite close to what I have! I wish I knew what they are, but no markings on them.

 

I need to find someone where I live that has one (Dyno), but I do not think we have anyone near. Is there a way to check on the web?

As to tearing into the carb, etc., I just love doing it. I have not rebuilt a motor, but there's a lot I can do. Most of it comes from working on cars when cars could be worked on by regular folk

Spinning here: IF I were to buy new exhaust, recommendations?

 

A two into one, Thunderheader, Vance and Hines Pro Pipe, Bassani Road Rage II, and the Two Brothers Racing Comp, and there is numerous others Rinehart, S&S Sidewinder

 

At least that's what I want, but pretty much all of them are not cheap!

 

I agree with doing the carb rebuild, I also have been doing them since the 80's starting with Quadrajets and Holleys. Good honest work, get to sit at the bench for a couple of hours, fairly relaxing. But after getting a good baseline to ride the thing, I like an expert to dial her in. You can get close, but they always get to the right spot.

Find the Dyno guy near you, ask him which pipes he likes that will allow for the best tune. You don't have to buy them from him, but he will know what works for your setup. Good luck finding a guy.