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Hello all,

Has anyone put dellorto PHBH 26s or PHBL carburetors on their 31/2 and if so what jetting worked for you? I want to use the stock airbox

I found this on another thread, with the center column as the recommendation. Can anyone confirm this is correct for the PHBL 25s?

Would anybody know?

I am sure most still have standard VHBs.

My main jet threading has stripped on my vhb and the whole thing seems like it’s getting a bit fragile/worn so I am looking for a more modern replacement.

I understandnthat, but these carbs are not something I have heard being used, so you would need to try it yourself. However, if you search the forum, there have been successful attempts with using other carbs, Mikuni I think.

R1100purist wrote: ↑29 Apr 2023 13:28 IMG_6431.png

I found this on another thread, with the center column as the recommendation. Can anyone confirm this is correct for the PHBL 25s?

I posted this one, worked fine for me

I used the centre column to work out the equivalent jetting for my Mikuni VM28's.

Hendre, thanks for the reply and confirmation. One thing I am not seeing on the euro carb website is the threaded intake in the PHBL 25s so I can transfer the current plastic “velocity stack” from the VHBZs…did you need to do this?

Also what needle did you end up using? The on in the middle column above? Or a different one?

70sbikes wrote: ↑30 Apr 2023 10:39 I used the centre column to work out the equivalent jetting for my Mikuni VM28's.

Great input, I think I saw your thread elsewhere. Mikunis we’re going to be my back up option as I would prefer to stay dellorto.

R1100purist wrote: ↑30 Apr 2023 10:39 Hendre, thanks for the reply and confirmation. One thing I am not seeing on the euro carb website is the threaded intake in the PHBL 25s so I can transfer the current plastic “velocity stack” from the VHBZs…did you need to do this?

Also what needle did you end up using? The on in the middle column above? Or a different one?

I had these on a bike i bought with these carbs, just noted the values as they worked fine on the K1. Cannot remember the velocity stack setup.

Hendre, thanks again. I should have rephrased my question, did you have any issues with the stock airbox connections?

Hi R1100purist,
I'm a bit late joining this thread. On my '86 K2 I've got stock VHBZ25 HS carbs, running 115 main jet and 50 idle jet with a stock airbox and stock 260 CM atomiser. Mine is a US model, without the emissions restriction setup. She runs quite happily with modern fuel (Australian 95 octane) and BP7ES plugs. I don't know jetting for the other carbs you mention though.
Cheers,
Fiona (Sydney)