Carb gurus: CV Carb needle proposition

[jonr]

Greetings all:

I have been searching far and wide on the GSR about increasing the jet size on my 82 GS1100G due to adding a 4-1 V&H pipe and still keeping the stock airbox. Near as I can tell, the general consensus is to go one up on the pilots and two up on the mains. Fine and dandy...

Then there is the infamous "shimming the needle" with washers should I need to raise that a bit for the mid-range. Coming up with small, thin washers is not all that difficult for someone in my trade, but I wonder if adding some extra notches to my needles would be better. I have a jeweler's lathe and can grind down one of my cut-off tools to take out a slot small enough to fit the e-clip used in the CV carbs.

So the big question is here: have fun with washers or go slot-crazy with the needles?

Thanks for your time.
Jon

 

[Steve]

If you have the tools, go for it. :dancing:

I would rather have slots, myself, and not worry about dropping little parts when trying to re-assemble the carb. :-k

You next question will probably involve spacing of the slots.
I will have to let someone with multi-slotted needle experience answer that one.
.

 

[jonr]

If you have the tools, go for it. :dancing:

I would rather have slots, myself, and not worry about dropping little parts when trying to re-assemble the carb. :-k

You next question will probably involve spacing of the slots.
I will have to let someone with multi-slotted needle experience answer that one.
.

Well, I have a set of VM carbs in my 78 GS750 and they are slotted. I was thinking of using that for reference.

However, if there are any Canadian GS owners with CV carbs who happen to have their needles out, please take a picture for me or give me a micrometer measurement. I'd be most grateful. Those lucky Canadians didn't have the same environmental standards we did at the time and their CV carb needles shipped with slots!

Jon

 

[TheCafeKid]

If this works out Jon, you could have a cult following in short order making these for us! you'd be legendary....neigh! You'd be a GOD!! hehehe

 

[twr1776]

John, I also have the V & H with the K & N filter and stock box on my 1000. I removed the OEM plastic spacer and used two of the Radio Shack washers for my needle position. The washers IMO are very easy to put in. I just pulled the tops of the carbs off and put them in while on the bike. I bumped the pilot jet two sizes and left the mains alone. My plugs are reading slightly rich at this point. I get some "burbeling on hard decell" but no heavy popping, I am going to bump the mains one size and see what I get. Brian has test ridden it and in his opinion it is very close on the jetting but still felt slightly rich to him. I would also rather be slightly rich than lean. My vote is to have fun with the washers, I am no carb expert but they were very easy to put in.

 

[Suzuki_Don]

Well, I have a set of VM carbs in my 78 GS750 and they are slotted. I was thinking of using that for reference.

However, if there are any Canadian GS owners with CV carbs who happen to have their needles out, please take a picture for me or give me a micrometer measurement. I'd be most grateful. Those lucky Canadians didn't have the same environmental standards we did at the time and their CV carb needles shipped with slots!

Jon

Hey the Canadians were not the only ones with grooves in their needles you know. I have a number of grooved CV needles in a drawer somewhere. If no one else chimes in I will measure tonight (Monday) and get a pic for you.

 

[jonr]

Hey the Canadians were not the only ones with grooves in their needles you know. I have a number of grooved CV needles in a drawer somewhere. If no one else chimes in I will measure tonight (Monday) and get a pic for you.

Go Aussies! Pics would be great Don. Thanks.

Tim, I may just try the washers, but sometimes I can't resist my lathe - especially when I have an extra set of carbs lying about and killing a needle won't give me a sleepless night...

J