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Discussion Starter #1
I'm supposed to know these things. :)

I finished re-assembly of the carb bank for the TBS yesterday and set the AF at 2 1/2 turns, as normal.

With new vacuum tees, and fuel rail and tee, new AF o-rings (thanks WSC), I (thought) I had a decent bench balance done before I re-installed the carbs.

After starting with full choke and attempting to set idle before I hooked up my new MotionPro carb liquid guage, I had come to the understanding that nothing was going to be done this way. Coffee Time!

Which is where I'm at now......

Questions for you guys if you care to weigh in on my ignorance.
*When setting the #1 and #3 butterfly, what size clip or bit do you use to gauge a good starting point?
*Or, do you set #2 first, since it's the main idle carb?
*When using this balance gauge , the tubes are placed at the vacuum ports on the carbs, correct?

I notice when I removed the carbs after the failed balance, there was copious amounts of fuel puddled in the intake rubbers. This was(?) probabaly done while I rand the bike without vacuum caps.

Any takers? :)
 

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I get that pooling of fuel in the intake rubbers too, also had it with the Mikunis - no idea why but the bike runs normally :dunno.

You can't set #2, just fiddle with the screw for nos 1 & 3 till all 3 are near enough the same. They don't need to be exact and you'll drive yourself nuts trying to get them perfect.

Rev the engine between screw turns to get it to "settle in" before adjusting some more.

Good luck :).

Oh yes, the tubes for the balance tool fit onto that brass bit centre in this pic -

 

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Discussion Starter #4
I found this video helpful.

https://youtu.be/DhentlraREU

Good luck
Thanks Johnny....
I've seen this video and find it to be quite confusing. It's telling the viewer to close all valves to max close, before re-install.

I don't see how a person can get a decent idle from that position.

What am I missing, here?
 

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(With the carbs off the bike) Adjust the idle setting so that the #2 throttle plate splits one of the four tiny holes in the throttle bore exactly in half. If your throttle plates are clean you can see the reflection of the hole in the plate. When the reflection completes the round hole you've cut it in half. Then, adjust the sync screws for #1 and #3 so you get the same sight picture. Done.
 

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Discussion Starter #6
(With the carbs off the bike) Adjust the idle setting so that the #2 throttle plate splits one of the four tiny holes in the throttle bore exactly in half. If your throttle plates are clean you can see the reflection of the hole in the plate. When the reflection completes the round hole you've cut it in half. Then, adjust the sync screws for #1 and #3 so you get the same sight picture. Done.
I like this.
Simple, to the point and clear as a bell.
 

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Discussion Starter #8
I balanced the carbs pretty much spot on per WSC's comment. It seems to be in sync, but who knows for sure.

/after unboxing and assembling the brand new MotionPro CarbTune, I'm sending the high maintenance tool back to FleaBay....what a piece of work!

New plugs are going in tomorrow.

An unrelated question...what might be a cause for smoke (or vapor) coming out of an exhaust when the bike is shut down? I noticed a bit of same vapor/smoke coming out of the vacuum port on top of #3 manifold.
 

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what might be a cause for smoke (or vapor) coming out of an exhaust when the bike is shut down? I noticed a bit of same vapor/smoke coming out of the vacuum port on top of #3 manifold.
When you shut the engine down, one cylinder stops with the exhaust valve open and another with the intake valve open. Whatever is left in the cylinder from the last combustion event is free to come out. (I may have the exact valve timing wrong, but you get the idea...)
 

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Discussion Starter #10
When you shut the engine down, one cylinder stops with the exhaust valve open and another with the intake valve open. Whatever is left in the cylinder from the last combustion event is free to come out. (I may have the exact valve timing wrong, but you get the idea...)
Makes good sense.
 

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..../after unboxing and assembling the brand new MotionPro CarbTune, I'm sending the high maintenance tool back to FleaBay....what a piece of work!....
I had the same experience with that tool. Sent it back and got a set of vacuum gauges.
I bought these;
http://www.ebay.com/itm/Pro-Fuel-Vacuum-Carburetor-Synchronizer-carb-sync-Gauge-GS-CB-KZ-XS-550-650-750-/222088427606?hash=item33b5807856:g:cdIAAOSw6oBXEaq7&item=222088427606&vxp=mtr

If you get a set, be sure to get ones with the attenuation knobs to control the needle bounce.
 

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I tried all the tools including the homemade tubing tool nothing works as well and as quick as the Morgan Carbtune tool. Best tool for the job and money well spent. It took 10 calendar days to arrive from the manufacturer.
 

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Purchased my Carbtune used off of Ebay for $50
I waited until the right one came up, but it was fresh and I couldn't be happier with the accuracy I'm able to dial it in. Tick over and smooth acceleration is the gain.

Money well spent!

Cheers
 

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Discussion Starter #15
$5 of plastic tubing and fittings, a wooden board and a quart of ATF gets you an unbeatable sync tool...
That's exactly what I'm doing, now. Marvel Mystery oil might be a better fluid.
 

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Discussion Starter #16 (Edited)
Having built a carb balance tool with tubing and ruler, my #1 carb shows no movement in oil, with #3 sucking the most, followed by #2.

Off with the carbs to check other possibilities which is questioned here > http://www.triumphrat.net/hinckley-classic-triples/561586-keihin-carb-rack-dis-assembly-and-clean-post7849978.html#poststop

I tried to find vacuum leaks using the carb cleaner route, and found a great stumble/stall at #1 and #2 diaphragm caps. Could the throttle bar cause vacuum loss, also?

With the first nicely warm day of the year, I'm really anxious to get out there and do a long ride to the Michigan dunes...before summer ends next week.
 

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I have the Motion Pro CarbTune, I've had it for a few years now and I think it works great. With installing the pods and mucking around with the carbs, especially this year, I've used it quite a bit and seems to be accurate. Better than the old mercury carb stix I have, could never get an accurate reading/adjustment with the mercury bouncing around, ballpark was about it.
 

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Discussion Starter #18
I have the Motion Pro CarbTune, I've had it for a few years now and I think it works great. With installing the pods and mucking around with the carbs, especially this year, I've used it quite a bit and seems to be accurate. Better than the old mercury carb stix I have, could never get an accurate reading/adjustment with the mercury bouncing around, ballpark was about it.
Turk, I sent the new Motion Pro back to the ebay seller (due to arrive tomorrow) because the thing wouldn't function ass directed. It sucked all the fluid in to #1.

I suppos eat this point, I'll go through and do another bench test and check the caps for leaks.
 

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I had the same issue with the Motion Pro.; also sent it back. It's hard to beat the vacuum gauges. As long as you get the ones with the attenuation knobs, you'll keep the needles from bouncing around.
 

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Discussion Starter #20
I had the same issue with the Motion Pro.; also sent it back. It's hard to beat the vacuum gauges. As long as you get the ones with the attenuation knobs, you'll keep the needles from bouncing around.

I'm going to stick with the DIY manometer for now. I've got the visual bench sync done and will check all of the caps and anything else that might be loosing vacuum.

What causes the fluid to be filled with air bubbles if there isn't a leak?
 
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