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Old 03-27-2013, 06:49 PM   #136
Kt-88
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Quote:
Originally Posted by supershaft View Post
I have seen the snorkels inside of Mikuni's a lot. From what I can tell, they all let dirt in like that. I think the pipe reducer is a better setup myself. Plus I have always wondered if the snorkels inside the carbs effects the atomizer and idle circuit ports in the bell mouth. I don't know for sure but I would think it might.
Off idle and lower throttle is noticeably improved vs the cone filters, which had to let more dirt through based off what I found in the carb mouth when I pulled them off. There was actual dirt in there.

I'll test the seal when I have what I consider to be a final setup.
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Old 03-27-2013, 07:00 PM   #137
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Originally Posted by Kt-88 View Post
Off idle and lower throttle is noticeably improved vs the cone filters, which had to let more dirt through based off what I found in the carb mouth when I pulled them off. There was actual dirt in there.

I'll test the seal when I have what I consider to be a final setup.
If that works great and if it doesn't there is the reducer route. Personally, I have always had way better luck getting beemers to motor out of low rpm with the stock airfilter setup. For some reason, beemers like long intake tracks. I am not the only one that thinks so. Look at all the race photos of beemers with long velocity stacks. Right now, my square airbox setup is basically doing nothing but holding my curved velocity stacks up. My stacks are bell mouthed JUST inside the box. I use to help with one damn fast airhead racer that had about the same setup excepting mine has a filter on top albeit with virtually no airbox top. Just enough to hold the filter on. Before a lot of mods, this latest very opened up setup would have killed low rpm performance.
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Old 03-27-2013, 08:48 PM   #138
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Quote:
Originally Posted by supershaft View Post
If that works great and if it doesn't there is the reducer route. Personally, I have always had way better luck getting beemers to motor out of low rpm with the stock airfilter setup. For some reason, beemers like long intake tracks. I am not the only one that thinks so. Look at all the race photos of beemers with long velocity stacks. Right now, my square airbox setup is basically doing nothing but holding my curved velocity stacks up. My stacks are bell mouthed JUST inside the box. I use to help with one damn fast airhead racer that had about the same setup excepting mine has a filter on top albeit with virtually no airbox top. Just enough to hold the filter on. Before a lot of mods, this latest very opened up setup would have killed low rpm performance.
I don't have any scientific data to support this besides ye olde butt dyno but I think you're exactly right. I think the carbs were also getting too much air and this helped them balance a bit better. Once I'm sure that the setup is as good as I'm going to get it I'll re-post the jetting and setting and resultant 0-60 times and 60-100 times, so we can try for some objective comparison.
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Old 03-27-2013, 11:05 PM   #139
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The VM34s have an OD of 44.5mm on the airbox side. 44.5mm is 1.751" so a 1 3/4 intake runner should fit nicely. I need to take a few measurements, but I bet something like this would work nicely:

http://www.siliconeintakes.com/produ...18b6cde636002b


EDIT: Actually the OD is 58mm, so scratch what I said above.
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Airhead Wrangler screwed with this post 03-29-2013 at 08:40 AM
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Old 03-28-2013, 01:36 AM   #140
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Quote:
Originally Posted by Airhead Wrangler View Post
The VM34s have an OD of 44.5mm on the airbox side. 44.5mm is 1.751" so a 1 3/4 intake runner should fit nicely. I need to take a few measurements, but I bet something like this would work nicely:

http://www.siliconeintakes.com/produ...18b6cde636002b
That may be the ticket. I'm sure that would look miles better than my haphazardly stuffed in tubes currently.
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Old 03-28-2013, 06:41 AM   #141
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Quote:
Originally Posted by Airhead Wrangler View Post
The VM34s have an OD of 44.5mm on the airbox side. 44.5mm is 1.751" so a 1 3/4 intake runner should fit nicely. I need to take a few measurements, but I bet something like this would work nicely:

http://www.siliconeintakes.com/produ...18b6cde636002b
Man, if I could have just a solid piece running from the clam shell to the carb, i'd be a happy man. There's a whopping SIX hose clamps just to secure this set up. Definitely isn't pretty.
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Old 03-28-2013, 06:53 AM   #142
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Here is a FWIW, despite SS's concerns.
I'm running VM 38's using the stock intake rubbers in the front and the stock elbows in the back.
The elbow is sealed inside the bellmouth, verified with propane.
The jetting sure feels spot on and there seem to be no atomization issues with the elbow in the bellmouth.
Mind you, I haven't tried it any other way, but the results speak for themselves.
Better power and better mileage than the Bings. Easy starts, lighter throttle pull are a nice benefit as well.
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Old 03-28-2013, 07:40 AM   #143
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Quote:
Originally Posted by Kai Ju View Post
Here is a FWIW, despite SS's concerns.
I'm running VM 38's using the stock intake rubbers in the front and the stock elbows in the back.
The elbow is sealed inside the bellmouth, verified with propane.
The jetting sure feels spot on and there seem to be no atomization issues with the elbow in the bellmouth.
Mind you, I haven't tried it any other way, but the results speak for themselves.
Better power and better mileage than the Bings. Easy starts, lighter throttle pull are a nice benefit as well.


As always real world results win out, but at least in theory, I'd agree with SS that there'd be reason to believe that sealing the intake runner on the inside of the carb mouth would affect airflow to the two air jets seen in the bottom right of the mouth. Keeping those unobstructed is critical to good atomization for both your idle and main circuits. I'd at least try another way to see if it makes a difference.
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Old 03-28-2013, 08:14 AM   #144
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Quote:
Originally Posted by Airhead Wrangler View Post

As always real world results win out, but at least in theory, I'd agree with SS that there'd be reason to believe that sealing the intake runner on the inside of the carb mouth would affect airflow to the two air jets seen in the bottom right of the mouth. Keeping those unobstructed is critical to good atomization for both your idle and main circuits. I'd at least try another way to see if it makes a difference.
Look at where the openings are located, they are in about 2-3 mm from the ID surface. The stock elbow ID is bigger than the OD that would be described by the circle that the openings are in. Also, the bellmouth on the VM 38's is deeper than how far the elbow sticks into the bellmouth. (Man, I hope that made sense)

The only way for me to try something different would be to get another set of elbows to play with. I don't want to be stuck with something that doesn't work as well, when I already have a solution that does. As you already pointed out, real worls results prevail.

I'll gladly accept donations in the interest of furthering the knowledge base

BTW, read your TDF thread last night, epic, awesome, jealous are just a few words that come to mind.
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Old 03-28-2013, 11:33 AM   #145
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I think I said that they seem to run alright like that but it is a concern of mine. I still think plumbing pipe reducers is the best route but that way works. I have just seen setups like that letting a lot of dirt in. I haven't seen pods letting a lot of dirt in but I sure have seen the stock clam shell and square airbox setups letting a lot of dirt in time and time again. Modified to fit and properly oiled K+N filters keep square airboxes spotless.
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Old 03-29-2013, 08:39 AM   #146
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Originally Posted by Airhead Wrangler View Post
The VM34s have an OD of 44.5mm on the airbox side.

Um, no they don't. It's 58mm. Scratch that.
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Old 03-29-2013, 08:42 AM   #147
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No update here yet. Still sorting out air leaks.
So far, still running like garbage, richening and leaning the mixture has no effect because there are still air leaks to hunt down, duh.

One of the reasons I'd like for that silicon elbow piece to work out

Maybe I can render and print something with ABS.
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Old 03-29-2013, 09:59 AM   #148
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airleaks

Airleaks on the airbox side really shouldn't influence the way the bike runs, unless they are massive.
Airleaks on the engine side on the other hand will completely mess with your metering.
Please verify that the instake stubs are tight and sealed to the head before you waste a whole bunch of time trying to jet the carbs.
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Old 03-29-2013, 10:02 AM   #149
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Quote:
Originally Posted by Kai Ju View Post
Airleaks on the airbox side really shouldn't influence the way the bike runs, unless they are massive.
Airleaks on the engine side on the other hand will completely mess with your metering.
Please verify that the instake stubs are tight and sealed to the head before you waste a whole bunch of time trying to jet the carbs.
That's what I'm currently doing. I went with the stock intake rubber there and just clamped it down a lot on the mikuni...that's probably causing mega leaks. I really need to do what Airhead Wrangler did and size that tube down with another, smaller one for a snug fit.
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Old 03-29-2013, 10:40 AM   #150
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so you're obviously not running 38s, are you ?
The 38s are essentially the same size as the 32 Bings.
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