Won't go above 60mph?!

peanut

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rafbobber702

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Thanks! I appreciate the info and I'll check that out.
 

rafbobber702

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I just ordered a new clear braided fuel line, thanks! Peanut

It's the first thing I'm fixing. I have a feeling that kink is restricting flow to left carb. Which is probably why it's cutting out the way it is....hopefully this will fix it.
 

suntosh

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I am having a very similar issue. Cruising on Highways at 65 it putters and wants to kind of stop but starts right back up. Should I change the fuel lines to braided ones.
 

suntosh

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Within the City I dont feel it . 4 -5 mile stretches spurts of 65 for a mile is fine but on the highway I guess yes the feel is that of a restricted flow. It chokes...
 

JesseeS

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Within the City I dont feel it . 4 -5 mile stretches spurts of 65 for a mile is fine but on the highway I guess yes the feel is that of a restricted flow. It chokes...
Unless your fuel lines are kinked like this individuals was in the thread, no. Do you know what jets are in your carbs and what your float height is set at? I’d start there
 

650Skull

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Check the fuel cap. It has a vent hole to stop the tank from creating a vacuum stopping the fuel. If the hole is parshily blocked it could cause a fuel restriction. When the gas cap vent hole is blocked completly the fuel stops=engine stops
 

suntosh

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suntosh

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I owned the bike for a 3 weeks. Out of which 2 were in a workshop getting the petcock rebuilt , dont believe the mechanic touched the carbs. He didnt even test ride the bike , he assumed rebuilding the petcock would solve problems and they did to a good extent.
 

jpdevol

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Of course we're not privy to the conversation with the mechanic. Seems he wasn't very thorough IMO.

Those appear to be original (to '81) Mikuni BS34 CV carbs and you have aftermarket mufflers and K&N "pleated style" gauze air filters. The latter have had problems, but can be tuned for if not blocking intake ports. Anyway, for proper performance the carbs should have been rejetted previously.

Good link here http://www.amckayltd.com/carbguide.pdf
 

suntosh

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jpdevol

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For pods, a long, straight foam one works best. Most of us run UNI pods. For the BS34 carbs, you'll need #UP4229 or UP4229ST (dual layer) .....



View attachment 213003

Pictured above are the dual layer version (ST) but you really don't need them. I only have them because I got them cheap from a local guy because they wouldn't fit his bobber.
The filter you linked are 5" long - probably too long to fit the area you have.
 

jpdevol

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To be thorough on this project, you'll need to remove and disassemble carbs. You've read the "carb guide".
You'll also need the tools shown in the guide and a manometer to synchronize them once reassembled.
Are you ready to tackle that?
 

suntosh

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To be thorough on this project, you'll need to remove and disassemble carbs. You've read the "carb guide".
You'll also need the tools shown in the guide and a manometer to synchronize them once reassembled.
Are you ready to tackle that?
I dont have the garage and the tools today maybe an year down the line. There are mechanics here I can find to work on them. I will need to give very specific parts based on the recommendations I gather here.

I saw the parts you are recommending. I am certain my Carbs only need cleaning and maybe I'll put newer fuel lines. But do you think upgrading to a VM34 is a good upgrade. I dont think I care about the 0 -100 speed.
 
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5twins

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Yes, you want the 4" long version, the UP4229. There's just enough room for it .....


UNIsInstalled.jpg


UNIsInstalled2.jpg


And for oiling them, don't get the special foam filter oil, it's too thick and can clog them. Simply use a 50-50 mix of motor oil and gas. I get the cheap straight 30 wt. from Walmart .....

UNIsOiled.jpg
 
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