Schism. Thats a loaded question. Probably 2-3 hours. I haven't done it yet. It's my winter project, along with apes.

I would really like to go pumpless but I have read too many posts concerning fuel starvation even with the 2.5 mm Suzuki needle and seat. Has anyone found a 4 mm or larger needle and seat assembly that will fit the stock carburetor?

The HSR42 comes standard with a 4.2 mm which is probably why it works ok without the pump. The pressure feed verson of the 42 uses a 2.3 mm needle and seat.

Area wise the stock HSR 42 float needle is over four times larger (13.85 vs 3.14 sq mm)than the stock carburetor while the Suzuki part is only about 1.8 sq mm larger.

Thanks for your help.

Mine ran great with just the Suzuki Jet and stock fuel valve, Adding the pingle valve cures any fuel starvation along with the high flow fuel filter. If I run the bowl dry, then hit the starter and turn on the fuel at the same time, it starts within a second, so I don't think you have to worry too much about fuel starvation.

Even with the stock set up I went about 8K miles and it only lacked fuel in a drag race at the top end, and at the time, I was jetted as lean as I could go.

Having just joined the "Pumpless" club, I can say it is a fairly easy mod, and one that can easily be reversed if you don't like it. I am doing mine one step at a time. First I simply removed the pump. It ran great except under extreme conditions. So I vented the cap. Same thing.
Now I am waiting for the needle valve assy. All the while the bike runs great under normal conditions so there is no down time. With the weather out here it might be a while before I find out if it starves due to low fuel. If so I will cut the petcock. Either way it is all pretty easy, the bike runs great, it looks fantastic, and if it never pukes again I will be a very happy camper.....

Some riders on the Road Star forum are checking to see whether the HSR42 4.2 mm needle and seat will fit the stock carburetor. Didn't Harleys run a 40 mm Mikuni on gravity feed? Wonder what size seat they used.

I've already tried it with the stock setup and couldn't get much above 75. Maybe it's because the 99's run a lower float than the newer bikes.

Thanks for your help.

All I know is the Tech article on how to go pumpless is right on. I have it done and I'm not puking anymore and I ain't going to mess with it. To question the MOD is to say it isn't going to work, when it does, many people have done it with great success, if your shy about doing it. Just don't.

Heck one guy on here somewhere went pumpless with the stock carb no New float valve, His pump went out on the road , he used a bic pen to join the hoses to bypass the pump and rode home.

Maybe you should just put a 42 on, They run great!

MS1700 wrote:
All I know is the Tech article on how to go pumpless is right on. I have it done and I'm not puking anymore and I ain't going to mess with it. To question the MOD is to say it isn't going to work, when it does, many people have done it with great success, if your shy about doing it. Just don't.

Heck one guy on here somewhere went pumpless with the stock carb no New float valve, His pump went out on the road , he used a bic pen to join the hoses to bypass the pump and rode home.

Maybe you should just put a 42 on, They run great!

And I've still got that pen piece in my toolbox as a souvenir... I ran for quite a while with no larger valve and no vented cap, just a new piece of hose, and no problems. Best mod I ever did done do.

RK

Sorry, I didn't mean to question the mod on your bike or anybody elses. I have tried it with the stock needle and MY bike , with a full tank, sucks the bowl dry at about 75 mph full throttle. The carb inlet screen was removed and there weren't any flow problems from the petcock or vent. With those results I can't see how 0.5 mm will make that much difference.

My float is adjusted to '99 specs 2-3 mm below mating surface which has to be done with the carb off the bike and level according to Mikuni. I called them when I found that that level can't be set with the carburetor on the bike.

I was just trying to find help for my particular situation. Sorry if I offended.

Scott B.

MS1700 wrote:

Heck one guy on here somewhere went pumpless with the stock carb no New float valve, His pump went out on the road , he used a bic pen to join the hoses to bypass the pump and rode home.



I had to do that once on the way back from a vacation trip up to Deadwood SD. My pump kept going out and I finally just bypassed the pump. I had to go slower then usual as I experience fuel starvation if I went any faster then 50 mph. Good thing I was riding backroads to home in Kansas when it finally happened.

When I got home I went ahead and went pumpless with all the mods. I love it.

texasscott1 wrote:
Sorry, I didn't mean to question the mod on your bike or anybody elses. I have tried it with the stock needle and MY bike , with a full tank, sucks the bowl dry at about 75 mph full throttle. The carb inlet screen was removed and there weren't any flow problems from the petcock or vent. With those results I can't see how 0.5 mm will make that much difference.

My float is adjusted to '99 specs 2-3 mm below mating surface which has to be done with the carb off the bike and level according to Mikuni. I called them when I found that that level can't be set with the carburetor on the bike.

I was just trying to find help for my particular situation. Sorry if I offended.

Scott B.

Oh, no WAY any offense taken here... Sometimes, the only way you'll know if one of these mods will even work for you is for you to just try it. The funny thing about these bikes is that even though they all come off the same assembly line "exactly" the same with the same parts, each has its own personality and works totally differently. A mod that works for some won't work for others. Doesn't matter that the parts involved are exactly the same. Doc couldn't go pumpless on his bike due to fuel starvation issues, so he went with the vacuum pump. Me, I can't starve the thing for fuel if I try (and I have).

This place is like a "salad bar of knowledge"...pick what you like and what works for you & leave the rest behind. And you can always come back for seconds...and thirds...and twenty-fifths...

RK