vm26ss float valve/needle refurb?

[Himble]

Hi folks, I recently scored a set of vm26ss carbs, complete in the rack for $25.....AUD!!
The float valve seats and needles are OEM Mikuni but the needles appear to be slightly scored where they sit in the base of the seat.
My question: Is it at all possible to reset the needle/seat in some way so it won't leak? Or better off to sell a kidney or 2 and purchase OEM replacements?
Aftermarket BTW are not an option for me....I already have some gifted to me and they're rubbish! And no, I don't know their source.

 

[zed1015]

It's hit and miss reseating worn float needles and the the old trick is lapping them with toothpaste or fine metal polish ( Solvol Autosol etc) but it's not really a long lasting fix.
The indented /scored tip can also be trued on a small lathe.
New OEM isn't that expensive in the long run ( especially with what the carb rack owes you ) and the VITON tipped ones are more forgiving.
There's plenty of genuine Mikuni suppliers that ship world wide.
Here's a couple that i use - NRP in the UK and Niche Cycles in the US..
The ones in the Japanese Keyster kits are also top quality and the only aftermarket ones i would use.

 

[GregT]

While everything Zed1015 posted is accurate, this is one case where I'd have to disagree with some of it.
Location makes a difference. In NZ and Oz, because of long supply times, we've learned to simply do things rather than wait.

I've been refacing the solid alloy float needles since the 80's. Did another set just 3 weeks ago. The aluminium needles are softer than the brass seats so any wear is on the needle face.
As they operate with line contact, refacing the needle - within +/- 3 degrees - is going to work just fine.

In the 90's I was looking after quite a few speedway TQ midgets - aussies will identify them as compact speedcars, no equivalent UK car class - which used the early GSXR750 mechanical flat slide carbs.
Between running on bumpy dirt and being trailered long distances to meetings, the float needles took a beating. Pressure fed methanol too.
I'd reface sometimes twice a season. Never had a problem.

 

[zed1015]

While everything Zed1015 posted is accurate, this is one case where I'd have to disagree with some of it.
Location makes a difference. In NZ and Oz, because of long supply times, we've learned to simply do things rather than wait.

I've been refacing the solid alloy float needles since the 80's. Did another set just 3 weeks ago. The aluminium needles are softer than the brass seats so any wear is on the needle face.
As they operate with line contact, refacing the needle - within +/- 3 degrees - is going to work just fine.

In the 90's I was looking after quite a few speedway TQ midgets - aussies will identify them as compact speedcars, no equivalent UK car class - which used the early GSXR750 mechanical flat slide carbs.
Between running on bumpy dirt and being trailered long distances to meetings, the float needles took a beating. Pressure fed methanol too.
I'd reface sometimes twice a season. Never had a problem.

I have to say that i don't see where we disagree with anything.
Everything you say is correct but the VM26ss rack OEM needles are either Viton tipped alloy or plated solid steel of which the latter being harder than the brass seat is trickier to re-seat and really needs re-facing rather than lapping which just barely touches the valve and mainly widens the brass seat contact area and reduces seat pressure which is why mentioned truing on a lathe.
Been there done that with the steel needles and even as an engineer they are a pain but sometimes you have to concede and buy new replacements which i hate to do being, Ahem! economical ( read miserly ) with my money.
I actually came up with a design for something akin to a miniature valve re-facer for the job but the need was so few and far between it never became reality.
If the OP has access to a small lathe or some other method of accurately grinding the tip it will be worth a try before having to source new ones.

 

[Himble]

Thanks for the responses zed1015 and GregT.
Given the "return on investment" probability, I'll probably bite the bullet and purchase OEM....if I can find someone somewhere who sells the right needle/seat assembly.
I had a look at the two sources you offered up zed, but couldn't identify exactly what I need. The Suzuki (Mikuni?) part nbr is 1337045010 but I've had no joy to date.
You mentioned Japanese Kester kits....I guess you mean Keyster. I've read conflicting reviews on them so I'm a tad wary.
Anyway, I'll do some more searching/researching! ositive:

 

[zed1015]

Hi, Himble.
Yes! Keyster .
My fat finger typing strikes again.
There was some issues with their kawasaki 2 stroke triples kits apparently but the ones for the 4 cyl VMs have been just fine.
I've rebuilt a couple of sets of VM's using entire Keyster internals and they run perfect.
The last one on some GS750 VM26's i bored out to 30mm and used their GS1000 VM28ss kit in them..
This is on a tuned 1075 motor with high lift cams etc and it behaves flawlessly from idle.
The float valve you need is the same on the VM26 and VM28 used on both GS Suzuki and Kawasaki KZ and others.
Kawasaki part - 16030-027
I work on both and they are essentially the same castings with 99% interchangeable parts.
There's plenty of Mikuni suppliers out there so you shouldn't have to look far.
Niche Cycles are very good at answering emails so it may be better just asking than searching their site which can be tricky.
I'll have a look around for suppliers closer to you and let you know if i find one.

 

[zed1015]

Didn't take long..
Found this supplier in AUS.
Carburettor Needle and seat 16030-017 16030-019 16030-025 16030-027 2.0 (z1spares.com.au)
Currently out of stock but was only $14 each so worth a call to see when they'll have them again.
It also shows the other part numbers used for the same valve so more chance of finding them.

 

[Himble]

Many thanks mate!

I had a look around some sites and some prices are outrageous!!
Fortunately, I found a local (Aus) seller...
https://www.motorcyclespareswarehou...roducts/kyv-03023-float-valve-needle-and-seat

I've purchased other bits from these guys, they are very responsive and helpful!

Hi, Himble.
Yes! Keyster .
My fat finger typing strikes again.
There was some issues with their kawasaki 2 stroke triples kits apparently but the ones for the 4 cyl VMs have been just fine.
I've rebuilt a couple of sets of VM's using entire Keyster internals and they run perfect.
The last one on some GS750 VM26's i bored out to 30mm and used their GS1000 VM28ss kit in them..
This is on a tuned 1075 motor with high lift cams etc and it behaves flawlessly from idle.
The float valve you need is the same on the VM26 and VM28 used on both GS Suzuki and Kawasaki KZ and others.
Kawasaki part - 16030-027
I work on both and they are essentially the same castings with 99% interchangeable parts.
There's plenty of Mikuni suppliers out there so you shouldn't have to look far.
Niche Cycles are very good at answering emails so it may be better just asking than searching their site which can be tricky.
I'll have a look around for suppliers closer to you and let you know if i find one.