I wouldn't start with the gearing (other than as Adrian suggests and dropping it a tooth), if you can only get 45 - 50 out of a 500 AVL engine there is something wrong with something. Timing is most likely ok with the TCI ignition and as you have upgraded the exhaust it can't be that, yes I would think you need to complement the exhaust with a better carb (sort of half the job done) but something is wrong, try a better iridium spark plug and take it out for a blast with no air filter. If you still have all the environmental stuff fitted there is a very good chance it is blowing excessive oil mist into the air filter and blocking it up, highly likely unless you have recently changed the air filter? Just pop the side panel off open the air filter box and remove the filter, quick run and do give it some, I would be surprised if it doesn't run better, you may find the air filter box is full of oil anyway. These were road tested at over 80 out of the box, other than the exhaust and carb mine is standard and happily goes straight up through the gears to 70 and will cruise there (still on the stock high gearing at present) for a 30 mile run (ok hands might tingle a bit!! ) but is very comfy at 65 for long runs.
In stock form I could get up to 70 without much strain, but from 70 on it was a very slow climb, I have touched 80mph on it one time when I first got it to see what it could do. It seemed that was it’s top speed.
I have since modified the exhaust, played with carb tuning, deleted the PAV, and put a good plug in it. The air filter is fine, I’m not getting hardly any oil blow by in there (surprisingly). I thought about going to a high flow filter, more on that in a minute…
I had trouble tuning the BS29 carb. It’s been awhile and I don’t exactly recall, but iirc I was using a 115 main and it was still looking a bit lean on the plug and my exhaust was turning purple. I went to a 120 main and then it was so rich it fowled a plug once but seemed pretty happy other than that. I dialed it back to a 118 main since then and it’s still a bit rich on the plug. I’ve also adjusted to a 17.5 pilot iirc and I’m on the lowest clip to put my needle at the highest point. At one point I actually shimmed the needle beyond that by a click.
With the 120 I ran for several hundred miles my top speed was around 70, but it was a slow climb after 55mph. Now with the 118 it’s still about a 70mph top speed but gets up to 60/65 rather easily. So yeah maybe a high flow air filter could lean it out a bit to get it more away from being slightly too rich as it is now.
I’ve clearly still got some fine tuning to sort through, but I’ll probably just toss the BS29 for a VM30 or VM32 if I can’t sort it with a sprocket.
A sprocket change is just so much easier than adapting a whole new aftermarket carb. And I’m not running that rich. The “lean burning” Electra here kept worrying me when I was trying to tune that carb since the plug was always bone white, so I’d rather be a bit rich and on the safe side ya know, I just want to be able to do 65 constantly without worrying about wearing the bike down, because that’s really all the riding I do on it tbh. Everywhere around here for a 500-1k+ mile radius is mainly country backroads where people drive 50-60mph+.
AZCal:
I don’t like the idea of the big bore kit because it’s expensive. I’d rather just buy another bike than spend all that money and do all that work. I can have custom made sprockets done cheaply by a place called Rebel Gears out here. They do amazing work. So you’re saying to stick with changing the rear sprocket?
I’m curious on why somebody would change one over the other? Is there a mathematical reason to do the engine sprocket over the wheel sprocket or vise versa? (For any bike I mean, not just our royals). Or is it just a preference thing? Like will doing one vs the other have a different feel in any way at all?
Adrian:
I’m about as average as average gets ha. I’m like 5’7” and weigh like 160lbs. So not tall and not heavy. I have read a forum post from another USA member who lived close to my area and said they switched to a 18T and loved it. It’s very hilly here in Tennessee. We have lots of mountains, though they’re not super steep or tall. In fact it’s the same mountains you all have over there, the oldest mountains in the world iirc, it’s believed we share them now because we used to share them back when Pangea existed (when all the continents were connected) so y’all got some of the same mountains. The Appalachian and the eastern Greenland mountains to be exact.
Perhaps I will try the 18T. I just worry it will be difficult to change if I ever want to go back. Right now I don’t mind because I have to take my whole primary innards apart to fix an oil leak, but it seems the rear would be easier to change yeah? Especially considering I can cheaply have a custom one made. Is there a reason people like to change the engine sprocket instead? Seems like a much more difficult job the way these bikes are set up. I do like the idea of the cam swap though. Perhaps I will attempt that one day
Topic: Gearing (Read 2069 times)