Dan's Solex type 32 PICB trial and review and dft comparison

Classic Goldwings

Help Support Classic Goldwings:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dan filipi

Well-known member
Staff member
Administrator
Moderator
Supporting Member
Joined
Dec 3, 2009
Messages
22,400
Reaction score
236
Location
Van Nuys Ca.
My Bike Models
1983 Interstate
2018 KLR 650
2018 BMW S1000 RR
My Bike Logs forum link
https://classicgoldwings.com/forums/dan-filipi.122/
This is a 1 barrel clone with 32mm bore and 25 mm barrel choke, purchased new.

More pics in my gallery gallery/album.php?album_id=10088

Why even consider a 1 barrel (or different carb) when the Weber 32/32 dft is reported to be "the best carb" and "good out of the box"?
Because the dft has an extremely rich idle circuit that is very difficult to lean up in my experience.
The 'real' idle mix screw had been removed from the original design when this carb was modified to meet EPA requirements for the engine it was going on. This includes 'Tom's' carb which I have tried also.
The dft is a great carb in all other aspects, I simply am not happy with it's rich idle that exaggerates a lopy-ness in the idle rpms and loads up the manifold.

This Solex is a neat little carb. I was able to get my 1200 engine running very good on it with the Cycle Innovations manifold where it was near impossible to get decent acceleration with the dft.

I really like the 'choke' design, which is not really a choke, rather a special 'enrichener' circuit.

Jets are accessible from the outside without opening the carb, except for the idle air bleed jet but 3 screws and the top is off to get at that.

Yesterdays ride about 60 miles I got 35 mpg with some stop and go traffic and hard head wind on the highway.
When coming to a stop, engine speed returns to idle good. I'm happy about that. DFT is often 'iffy' that it might and sometimes would die.

Acceleration is good and smooth, though there is a definite reduction from 2 barrel dft to 1 barrel but the 1 barrel is fully capable of running up 8000 rpm and beyond.
Low end torque 1500-2000 rpm seems smoother with less engine chugging/lugging.

Though not perfect, I like this carb and impressed that it does so good on the CI manifold, of which I have added sleeves into to reduce the runner inside diameter.
Next I'll be putting my runners with the type 4 plenum on to see how that does.
I'm hopeful I can get a near perfect idle with this combination.

If anyone else has experience with this carb I'd like to hear about it.
 
This is before any jetting:

[video]https://youtu.be/r6gsscdBOrg[/video]

This is after my latest jetting:

[video]https://youtu.be/J5KBXfXjb6c[/video]

I'm trying to find what happened to those 2 videos. Here is another

[video]https://www.youtube.com/watch?v=etetl9tZ4z8[/video]
 
Quieter and idles better at low RPM, sound as if the pump circuit was working it would be tit`s. I would keep it on that manifold till you get the bugs out with pumping and or jets, dont think the other manifold is going to make a drastic difference like tuning the carb will..How are the plugs burning?
 
I am getting a very slight hesitation on slow rpm take off's which I blame on the very lean idle jet it's at now. This jet affects the idle tranistion gas feed.
Proper rpm takeoff there is no hesitation.

The accel pump in carbs are intended to eliminate stumble during fast acceleration. There is no stumble so I see no need to waste gas when it's not needed.

Plugs were black from all the rich running I was getting out of the dft.
they are cleaning up and looking tan now.
 
I see your point. Do you think the idle circuit was designed with the pump in mind knowing that as soon as the throttle is hit it gets a shot? I can see what you mean at highway speeds but it has to come off idle more regularly then changing highway speeds..
Just wondering.
 
The accelerator pump is a good topic all on its own.

The dft pumps A LOT of gas in, which is great for cold starts but once warmed up not needed at all.
I was riding along on a bumpy freeway when it occurred to me the bumps were making me twist the throttle back and forth. Duplicating that movement at a stop I saw the accel pump squirting. For every increase in mpg, each drop of gas saving anywhere you can get it gets increasingly critical. For this reason I'm leaving the Solex pump non-operational and with it's cold start enrichener design there is no need for it.
The very slight stumble, which may or may not have to do with this, is really a non issue.
 
I got ya, I wonder if in the end you can jet down the accelerator pump, maybe a small jet or ferrill in the "to carb" port or a spring on the linkage to regulate it.
Interesting carb though.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=146430#p146430:21sxv7k1 said:
zman » less than a minute ago[/url]":21sxv7k1]
I got ya, I wonder if in the end you can jet down the accelerator pump, maybe a small jet or ferrill in the "to carb" port or a spring on the linkage to regulate it.
Interesting carb though.
Nice feature of this carb is the accel pump has a separate jet than can be modded up or down.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=146431#p146431:272m0374 said:
dan filipi » Thu Apr 16, 2015 10:17 am[/url]":272m0374]
[url=https://classicgoldwings.com/forum/viewtopic.php?p=146430#p146430:272m0374 said:
zman » less than a minute ago[/url]":272m0374]
I got ya, I wonder if in the end you can jet down the accelerator pump, maybe a small jet or ferrill in the "to carb" port or a spring on the linkage to regulate it.
Interesting carb though.
Nice feature of this carb is the accel pump has a separate jet than can be modded up or down.
Perfect!...For some reason I like this carb better then others, maybe cause it is less cluttered and simple.
 
Great report. Sounds to me like this carb has great promise. Two stage carbs are nice for extending the power band if one can be found adaptable. Maybe there will be some way found to replace the DFT's missing mix screw.
The list of workable carbs is getting longer. I bought a used solex very similar to yours to try on mine.
 
Howdy Dan ! do you have a link for that carb? as you know, i run mine on the primary of the carb only as i don't see any need for the second bbl the way i ride. I would love to grab 1 like you got and play with it! i get killer mpg now with my set up but would loke a 1 bbl to tune the idle rich condition . Nice work Man!
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=146462#p146462:3qadgng7 said:
Omega Man » Today, 12:39 pm[/url]":3qadgng7]
So if I'm reading this right the Solex might just be a much better choice all around than the DFT virtually changing everything we know about the SCC?

~O~

Well there are good and bad in both carbs.
The Solex has been much easier to fine tune than the dft.
I learned a lot from the dft and may miss the second barrel but I do like that this carb feels better matched to the engine size and it does have enough power.

Some would say there is no fine tuning needed to bolt and go with a dft on a oldwing. I say that's hogwash.
A grossly over rich idle washes oil from the cylinders which is not good, therefore it is not a straight up bolt on carb.
Still some are happy with the way the dft runs on their bike, which is great but it's not good enough for me.
It is ludicrous to think a carb that is tuned mostly for a specific engine in a CAR with it's extra loads like air conditioning, power steering etc would be tuned to run proper out of the box on an oldwing.

I am not out to change anyone's mind to run a dft. Everyone is free to run whatever carb they like. The more options we have the better.
What I am trying to do is dispel the rumors about the single carb conversion, unfortunately these rumors are like a fast spreading virus of hearsay and opinions by those that have never even explored a conversion and know nothing of the inner workings of a carburetor or have done any test jetting changes.
I only know what I have personally tried, and frankly those are the only one's I trust without seeing first hand the results.

I'll get off my soap box now sorry, bugs me there is so much wrong information on other forums mis-leading people by those with big words that talk themselves up as an authority like they even know anything. This hurts the credibility of forums.

Ebay Link to Solex

Filter arrived.
It's nice enjoying Christmas all year 'round.


 
I just talked to the seller and said I should give heads up these are returned carbs for whatever reason a carb gets returned.
Some may have a damaged or missing part or other blemish but they are sold as is.
Also said they are selling fast so he may run out.
 
Other sellers have very similar solex carbs for sale. Seems they are still making this size and style carb. I've seen prices up to $189 so far.
 
Top