jets question

[dragonslayer]

 
  Ok so now I'll show my age.Many years ago when I worked on European cars there was no such deal as going to your parts store and getting replacement jets for carbs so we just drilled them larger.Has anybody done that on their Valk and if so what size drills did you use?Sometimes money gets alittle tight so looking for an alternative.TIA

[Patrick]

I used to drill jets all the time, not so much any more, no need to.
I did drill them on the Valk many years ago on the modified bike, so long ago, that I can't tell you anything.

[Ricky-D]

well, first you have to determine what exactly the number on the jets mean.

It could be any one of many answers.

***

[gordonv]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

[Patrick]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

Yep, exactly. If one is going to be a jet driller outer, they need to have a goodly supply of drills.

[Ricky-D]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

I sure hope no one would try this bit of advise.

***

[Patrick]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

I sure hope no one would try this bit of advise.

***

Actually thats kinda sorta how its done.  Some jets aren't marked. So, you find a drill that fits the best. Measure it, don't trust its markings. If the jet is to be bigger, figure out how much bigger you want it and drill it to that size. If you want it smaller, solder it closed and then drill to your new size.
Once the right size is figured out, its nice to install new jets of that size. But, usually I've been too lazy to do that until the carburetor has to come apart again.

[gordonv]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

I sure hope no one would try this bit of advise.

***

I never did say to do this. I only asked how it would be done. Read the original post and the first reply. Each say that they have drilled their jets in the past. I agree with Patrick, no need to. I take it that is because you can buy them in know sizes.

Unless I had a means of measuring the performance change (a dyno) and did measure and document that performance, I wouldn't even change my jets.

[Patrick]

Wouldn't you just take your jet to a store with good quality drill bits, find one that fits the current size, and then move one or 2 sizes larger, drill, and try it out?

I sure hope no one would try this bit of advise.

***

I never did say to do this. I only asked how it would be done. Read the original post and the first reply. Each say that they have drilled their jets in the past. I agree with Patrick, no need to. I take it that is because you can buy them in know sizes.

Unless I had a means of measuring the performance change (a dyno) and did measure and document that performance, I wouldn't even change my jets.

Years ago it was easier [and cheaper and faster] to just drill the jets until you got the results you were looking for. Thats back in the days when we needed and had access to a wheel dyno. After awhile you kinda know what will do what.

[98valk]

unless u are opening up the air box the stock OEM 100 main jet is more than enough.
oem pilot is more than enough just open the idle mixture screw max 4 turns, need more than 4 turns then go to larger PJ.
www.factorypro.com go to tech section great carb tuning instructions.

[dragonslayer]

 

  Great feedback,I guess it'll be a trip to a good hardware store to get a drill.Thinking I may leave the mains asis and just open the slows just a hair.Thanks for all your input.

[Patrick]

  Great feedback,I guess it'll be a trip to a good hardware store to get a drill.Thinking I may leave the mains asis and just open the slows just a hair.Thanks for all your input.

Thats fine. It just depends on what a 'hair' is.
As far as the Valk is concerned, the mains are already a bit rich. The lows are a bit lean, but, a couple thousands of an inch are all thats needed. If you can't find a drill the exact size, just buy new ones from Sudco.

[Ricky-D]

Well, if #35 and #38 is mm, then I would think #35 is .35mm and #38 is .38mm.

The difference is .03mm which is .0012". So if you start drilling out as suggested,

you will be going way bigger than necessary.

Wire gauge drill bits would be the best choice for this exercise.

Best choice would be to simply get #38 slow jets.

I don't recommend to do either.

***

[98valk]

  Great feedback,I guess it'll be a trip to a good hardware store to get a drill.Thinking I may leave the mains asis and just open the slows just a hair.Thanks for all your input.

just turn open the idle mixture screw 1 turn and see the difference, no need to replace PJ.

[gordonv]

Wire gauge drill bits would be the best choice for this exercise.

That is what I thought I would use. Are they actually files more than a drill?

[Ricky-D]

Nope.  Actually true drill bits.

A magnifying glass will reveal the detail.

***

[Patrick]

Wire gauge drill bits would be the best choice for this exercise.

That is what I thought I would use. Are they actually files more than a drill?

They are drills but you can use a pin vise and drill by hand if you wish.

[Attic Rat]

I agree with everything that CA had to say on this matter

[Farther]

This seems like a solution to a nonexistent problem.

[Patrick]

This seems like a solution to a nonexistent problem.

For a Valkyrie thats true.


But sometimes its just fun to find fixes for problems that don't exist. Whats the old saw, if it ain't broke fix it till it is.

[98valk]

Valkyrie owners are problem solvers. Even if our solution has nothing to do with your problem.