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Discussion Starter #1
Hey guys, coming home from a ride the other day, the bike started making a different sound than usual, a kind of a popping exhaust noise in addition to the normal gurgle of the silmoto pipes, and no power until it about 5k rpm. I got the bike home and had to put it in the garage for a bit because of a business trip. Finally getting around to taking a look at it. It starts okay, and idles pretty well, but with that louder popping in the exhaust note, and it is very sluggish with almost no power until it hits 5k rpms, then it rips your arms off... any ideas?
 

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I would guess the ebs relais or a bad sparkplug...
 

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Hey guys, coming home from a ride the other day, the bike started making a different sound than usual, a kind of a popping exhaust noise in addition to the normal gurgle of the silmoto pipes, and no power until it about 5k rpm. I got the bike home and had to put it in the garage for a bit because of a business trip. Finally getting around to taking a look at it. It starts okay, and idles pretty well, but with that louder popping in the exhaust note, and it is very sluggish with almost no power until it hits 5k rpms, then it rips your arms off... any ideas?

If you go to the hospital a nice doctor will fix your arms back for you lol

I would definitely check the plugs and try to see which cylinder is missing first and then swap the plugs over and see wots wot.

Check the vacuum hoses aren't leaking at the caps etc and that he intake rubbers aren't loose anywhere.

It could just have caught a cold Ian as you guys aren't used to the cold down there are ya ?:stickpoke

joe
 

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My money's on a bad spark plug, but as Joe said, you may have a vacuum leak
You know, from experience we have probably all learned that it is very difficult to diagnose at a distance.

My own strategy is to go through a logical sequence fuel, air, spark to root out the problem by elimination rather than trying to stab at guessing what it is..which is what we mostly tend to do.

That way the tank will be off once rather than on and off like a tarts knickers on Friday night/ :naughty:
 

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just got off the phone with Ian......

his father has an IR pyrometer....hold a steady RPM and shoot the pipes that will tell him which cylinder

air leak! not plugs, it runs on top and the exhaust pops

:drummer:
 

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Discussion Starter #7
Thanks again!

just got off the phone with Ian......

his father has an IR pyrometer....hold a steady RPM and shoot the pipes that will tell him which cylinder

air leak! not plugs, it runs on top and the exhaust pops

:drummer:
Once again, Noel is dead on with the diagnosis.

Pyrometer read about 100f on cylinder two while the others quickly got into the 300f range. Pulled the tank and inspected, quickly finding the loose vacuum cap.

Mixed some JB Weld and sealed those bitches off at the head.

Everything is back to smooth as a top!

Thanks yet again for your help Noel. Once again taking time from your day to give a personal phone call to help out another member of the forum.

:f4::yo::f4::yo::f4::yo::f4:
 

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Ian;
I've had problems with the vacuum caps.....enough Chinese crap

I pulled the brass nipples out of the manifolds and epoxied the holes closed.....

ask the guys at Bubba IV how fast I synced the TBs with my Uni-Syn, been using the same one since 1959

http://www.mgexp.com/phile/1/111786/UniSyn_tool_parts.jpg

yes, you have to plug the stupid holes in the air horns:jerkoff:
 

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Noel, that link won't let me in .
I am in the market for a decent sync setup....
 

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Noel, that link won't let me in .
I am in the market for a decent sync setup....
Chuck;
the link works on my desktop but not on my Droid go figure?

you can get the Uni-Syn at AutoZone

:drummer:
 

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remember on MVs do not change the throttle stop on #3 & 4, you'll have to reset TPS, adjust #1 & 2 opening with a narrow tip feeler gauge to equal # 3 & 4, then go to the bypass screws

just like doing the 6, 2 barrel Webers on a Ferrari, do the linkage first...... then bypass screws

think about using Carb Sticks on a 12 cylinder:jsm::jsm::jsm::jsm:

vs a Uni-Syn :naughty:

I left out the part about mixture screws intentionally
 

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Last question, then back to the regularly scheduled thread.....do you use four of those, or do you move one from TB to TB?
 

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Chuck;
you use one, no mechanical or electrical error possible.....

didn't you see me do Carl's SPR at Bubba IV?

Donsy adjusted the linkage between 1&2 and 3&4 so the throttle gaps were the same.....you could see they were wrong

most I did was ~1/8-1/4 turn on the bypass on 1 cylinder the other 2 were ~1/16 turn

don't forget to epoxy the holes in the air horns

:popcorn:
 
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