TOPIC:

Well that was... unfortunate. It occurs to me that after I adjusted all of the mixtures screws inward, I forgot to make any adjustments based on the color of the spark plugs, except I think on #1. Ah well it was still running better than last week, guess I'll re-check the plugs again tomorrow after I get home.

All right, made some more small adjustments to the mixture screws last night. It's running pretty smoothly although there's still some issues. From idle if I suddenly crank the throttle there is a short hesitation and it still seems to be a little slow coming back down again (although nowhere near as slow as when I was running really lean). All four plugs are very close to identical now -- brownish with a slight coloration of the insulator, maybe a little bit of black soot around the outer edge but they're not wet and there's no granular build up on them. I believe all four mixture screws are within about 1.5 turns of each other and probably average about three turns open. Since I continually hear about the BS34's being notorious for running lean I've been trying to err on the rich side with my adjustments.

The other symptoms I'm seeing are in the exhaust. Feeling the output at idle, the right side feels smooth, almost a continuous output, but the left side has a definite chuff-chuff feel to it and is running noticeably cooler. I'm not quite sure what that is about since the plugs indicate all four cylinders are firing fairly equally, unless it's just the engine timing I'm feeling? There's also more of that "Harley" sound coming from the left side during acceleration. I am no longer getting any backfiring in the pipes, except very slightly when I accelerate really hard and then let it coast back down (low popping but no actual explosive backfiring).

I think the vacuum balancing went well. After multiple adjustments across the board while idling at about 1200rpm I think I have all four cylinders within 1/2 point of each other. I didn't mention it before but after the vacuum adjustment I decided to take all the mixture screws back to stock (2.5 turns) and start from scratch on adjusting them. I think they are pretty close now so I'm not sure what else to look at.

Any suggestions?

One other issue I'm starting to have trouble with... this bike feels kind of low to me. I'm just under 6' tall but I'm all legs. So when I'm sitting on the bike the top of my legs are even with the ground and my knees are forward of my feet. It makes me feel a bit cramped and I have trouble moving my feet around on the pedals, but I don't really see any way to change that. Maybe this is why so many people go for bobbers -- to gain extra leg room?

Slight bog when suddenly opening the throttle, slow to retun to idle, and popping in the exhaust on deceleration all indicate a lean mixture.

The seating position is typical of Japanese cruisers, and is actually more comfortable on long hauls than the feet-forward position of typical U.S. cruisers. At least for most folks. Personally, I prefer to have my feet farther back, and my torso leaned slightly forward, as that puts much less pressure on my lower back than the feet-forward , ape-hanger position does.

P. S. If your fuel has ethanol in it, plug readings can be inconclusive .

Yeah I was wondering if maybe I was still on the lean side. Would it help if I pulled out all four screws another half turn or so? That's the reason they are all centered around 3 turns now instead of the factory 2.5, because I was pretty sure it was still lean previously. And yes, 10% ethanol <pouts> so what can I do instead of plug readings? I've tried turning the screws in and out a couple turns and I think I only heard an rpm change on one of the cylinders. Ugh it just occurred to me, are these engines even set up to run unleaded fuel since we don't have regular any more?

On my Yamaha I used to put my feet on the back pegs when I was cruising. Tried that on this bike and it's even more cramped. When I make the new seat I might have to make it flat to give me space to scoot back.

Making good progress. I made another slight adjustment last night and then opened up all four screws another half turn. It was running pretty smooth today so I'm going to leave it there for a bit and see what happens. And I really gotta get that oil change done this weekend! I'm putting a lot of miles on the bike now, went over 600 today... if I can remember where I found the oil filter at.

I don't have proper brackets so I'm hanging my pipes by bailing wire (literally, from the farm supply store up the street!) and one of them broke today. I doubled up the wire this time, but I'm thinking there might actually be enough room to put a bend near the end of the headers and get the angle I want for the muffler. And it looks like the muffler hanger bracket would line up perfectly to the bolt on the frame. The mufflers are already pulled up pretty tight now within what flex they have, but are still pretty straight to the ground. One of these days I'll get that bit finished up.

Tried re-painting the clearcoat on the tank this weekend and failed once again. This time it was because I didn't get the sag sanded down far enough to erase the line, so as soon as I hit it with the first coat of clear the sag was painfully obvious again. I did however manage to get the top and other side of the tank finished, so I only need to focus on this one side now. I started working on sanding it again yesterday with 320-grit paper in my sanding block. Seems to be taking out a lot of material and yet I can still feel the roll of the sag. Ah well I'll keep working on it, try to get that finished up tonight. We have more rain coming in for the weekend so I need to get this cleared once more before then.

The carb adjustments are getting really close. I made more slight adjustments this weekend, only opening some screws and not closing any of them. Still going by the plug colors as I have nothing else to judge by, but it looks like 1-2 are running richer than 3-4. It's feeling a little better each time though and now it is even running fairly decently on cold mornings (in the upper 50's). I'm also noticing during the hot days that I usually don't have to choke it for a cold start, and it seems like the radiated heat from the head is more even between the left and right side now.

Finally got the oil changed this weekend. I still can't find any 10W40 with the zinc additive, so I'm running Valvoline 20W50. The oil that came out was fairly dirty but there was no sign of ground metal so that was a relief. Otherwise I should be pretty well set to sit back and cruise through the Summer now.

The gas leaks have sealed up finally. No more gas from the tank or the carbs draining on the ground. Makes me wonder if something got through the filter and jammed up one of the floats until the engine got a good run? The only thing I have to deal with now is the oil leaks around the top of the head. Besides leaks from two of the four side plugs, I've also seen some seepage around the center of the head. I've already gone back and re-torqued the large head bolts, but I should probably also check the smaller bolts around the cam cover. I picked up an inch-pound torque wrench at Harbor Freight last weekend for $10 on sale. Wish I'd had it when I did the motor assembly but at least now I can torque those smaller bolts more accurately.

Finally got some pics with the new tank on the bike...





Went back out this afternoon and noticed a gas drip under the bike. Last time this happened, I pulled the bike upright and gas drained out of the intake box, so I thought I'd check that to see how bad the leak was... and I pushed the bike all the way over. #@!#$@!#$@

Of course I took out the turn signals, have some minor scraping on the timing cover, and discovered that the clearcoat on the tank is NOT fuel-resistant despite being the same stuff as the paint on my engine. I guess clearcoat just isn't made very well. On the other hand, the paint itself wasn't even touched by the gas after it ran through the clear.

I threw on some cheap LED signals so I can ride it to work tomorrow. Looks like garbage but it'll keep me going until I can get some proper replacements.

Bummer. That bike is just begging for a duck tail.
Steve

Yes it is! I have the tail and the seat pan to modify so it will fit over the tail. That will probably be a Winter project though. Would have been nice if there were a seat for this year that actually fit around a tail, but oh well...

Sweet, I found a seller in the US that has the turn signals, says I should have them by Tuesday. If they are truly shipping locally then I could possibly even see them this weekend.

I scraped a bit at the gummed up clearcoat on the tank, it looks like the gummy stuff may scrape right off. No time to mess with it tonight, but maybe I can get it down to where I can buff the paint again and at least cover up the ugly black streaks where the clear melted. I did say this was a *test* to see how well the paint holds up on the gas tank...

Yes Steve, a duck tail would be a real good looking improvement!!!

Hi Shdwdrgn, you should try using 2K clear coat next time. It is gas resistant, so less worries about spilling gas onto it. More durable too.