G'day.

I'mm looking for some larger jets to try on my 1000, I'm running twin 40PHH Type-R's although I'm sure any of the other Solex Mikuni models have the same jets.

Looking for Main Air Jets and Main Jets.

Chris

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What sizes are you running atm?. Are you seeing problems at WOT. I take it the idle and progression circuits are fine in terms of fuel metering...

this guy has quite a few Solex Mikuni jets.

Solex jets

Hello Benny, jetting as follows;

Main Air Jet 160 160 160 160
Main Jet 135 135 135 135
Bleep Pipe NA NA NA NA
Jet Block 8 8 8 8
Pilot Jet 65 63.8 65 63.8
Pump Nozzle 40 40 40 40


I am getting a couple of hesitations, and yes when I push for WOT it's sorta gargles and then kicks in. I took it for a drive and it was fairly rough.

I am also getting a few pops here and there - does this mean they are running lean?

Here is the last thread I started when having issues with idling (which I have almost sorted out). I cleaned the pump nozzles but this didn't change THAT much.

EDIT: here is a better list;

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from the description it sounds like its going rich on the tail end of the progression cct, at the cross over point when the main cct kicks in.
The air jet size may benefit from going up a couple of sizes to 180.[but that really only influences the mixture at high revs on the main cct] Whats the engine capacity again? 1200 or 1400? Also does the Pilot jet = idle jet?

And lastly whats the choke tube and Aux vent sizes?

cheers
benny

Cool, thanks for the advice.

I am unsure of Auxiliary vent size. I THINK the chokes are 31mm, actaully I'm positive. Engine is about 1220cc.

I have tried to balance them as best I can but this is a little off as well, until I can get a synchronizing tool.

I can adjust the accelerator pump to supply a little more fuel, would this help? At the moment it is at the middle setting of the three options.

Ok, good start on the choke tube size 31mm, the smaller the better on a street engine, [maintains mixture speeds] as majority of your driving will be on the idle/progression ccts.

On such a smaller capacity engine the mains currently installed seem to be too large at a educated guess I would be looking at 115 - 130 size, pump jets 30 - 40 and idle jets [curious why they are listed as different sizes for each barrel of the carb]

Another point to consider with the pump cct is the duration that the fuel is delivered and not just the volume of fuel.

Were these carbs originally off a Toyota 18RG twin cam?

fuel pump pressure I wouldn't exceed 3PSI [if they are anything like Webers]

Double ccheck the fuel float level.

Found this handt site also. Mikuni carbs

I'm not too sure to tell you the truth.

These are the uncommon Type-R PHH, that I bought years ago 'jetted to suit 1400-1500cc' so your probably right about the main jet. The Type-T (for toyota) are the more common ones, they do however share the same jets.

I reckon I might just have to invest in a handful of jets and start some experimenting.

As for the different Pilot Jet sizes, that seems to be a common thing on these carbs, where one side is different to the other. I might just put the same size in all round.

I had a quick look online at a few jetting tables for the PHH carbs. seems their is a limited selection for idle jets. I would go for the 55 [seems to be the smallest ones listed] One noticable difference between Solex and Weber in regards to Idle jets is that the "Air bleed" hole is fixed in the body of the carb unlike Weber, where the "Air bleed" hole is part of the brass jet itself.




To save a few dollars maybe chase up another pair of 63.8's to match the existing pair you already have.

Yeah I've just emailed that bloke to get some jets sorted. I was hoping to borrow some off someone so I didn't have to buy varying sizes but I guess that's the best way to find out what suits them.

Thanks for all the help benny, I'll hopefully get the car on the road before too long.

They are a good carb and I'm pretty happy with them, but I just want to get the damned thing on the road!

Going off the jetting table for the Solex's from Toyotas seems there are smaller choke tubes [28mm] and smaller idle jets aswell.

Mikuni Solex jetting table