Jump to content
IGNORED

1 carb


Recommended Posts

Average speed is 110 km/h (68,35 mph) . to measure a compression there is nothing. 130 km/h - 4000 turns. The throttle is open on 1/3. I will tell so that it became worse not)

Edited by KISA
Link to comment
Share on other sites

Would a progressive 2bbl carb like one of the webers from a 2.3l pinto engine be a better option than the 1 bbl carb?

 

I believe it would, I plan to find out but it's going to be a little bit of time before I'm ready to start a prototype manifold. I have to get moved first. I'm planning on using a progressive 32/36 and I have a couple old Dells and a few other Weber cores to play with.

 

I'll bet that PICT delivers some pretty nice torque, but I also believe for optimal top end performance at least one more throat would be beneficial. I've used the progressive Webers on old Ford 4s, Datsuns, Toyotas and VW (air and H2O), but never on a bike. I have a very strong hunch that it will be an ideal conversion, the only stopping point I see is I'm not willing to sacrifice MPG, and it seems that the OEM rack generally gives up about 40mpg if dialed in correctly. I'm convinced that with some dialing and jetting (there are many ways to tailor a Weber) it will work (maybe) nearly as well as the OEM rack, get comparable MPG and be more reliable with less maintenance, also servicing it should be much easier than wrestling with the OEM rack.

 

I'm so convinced that as soon as I get some cleared shop space this is my first project. I do not feel this would be ideal for a Vmax but for a Venture, I'm very optimistic. It's all hunch at this point, but I'm very bent on proving or debunking this. I've never understood why there is no Weber conversion on the market already, maybe I'll learn why.

Link to comment
Share on other sites

It is a dynamic flow problem first, then you can scale the jetting!

 

You must consider throttle plate angles - or you starve and flood the jugs because of the lack of plenum, spacing above the plenum, verses the effect of plate angle (s)... so one side floods the other starves

Patch

Link to comment
Share on other sites

It was passed by 100 km (a photo 1) on the route and 10 around the city (foto2). Main Jet 140. On it I will also stop.

Goes well, about 170 km/h dispersed and there was a gas reserve.

[ATTACH=CONFIG]116960[/ATTACH][ATTACH=CONFIG]116961[/ATTACH]

Link to comment
Share on other sites

Nice fork covers Kisa!

 

As you adjust your jets, keep an eye on the temperature or check the exhaust temperatures. Best to continue checking the spark plugs all 4 and note the changes and colors down.

Patch

Link to comment
Share on other sites

i have been playing around with the idea of a log style manifold with a 32/36 webber. I did a bad cad drawing. I don't have a webber here to take measurements so its kind of a educated guess on that aspect. i would use 16g steel preferably stainless.

manifold.jpg

Link to comment
Share on other sites

i have been playing around with the idea of a log style manifold with a 32/36 webber. I did a bad cad drawing. I don't have a webber here to take measurements so its kind of a educated guess on that aspect. i would use 16g steel preferably stainless.

 

For me and others like minded combustion is my favorite part of the sport, also where I have made some of my most costly mistakes over many decades! So I certainly understand the desire to mod and accomplish but, it doesn't happen by luck it really takes a lot of study then, your projects become the classroom. Without the study its difficult to understand where the mistakes are, and to use a term we "wash out"!

 

I have a post somewhere on the site where I laid out some thoughts about a couple of conversions I would like to do. One on a V4 and the other a straight 4, both will require head work and flow monitoring. Starting with how they are and then how I can improve on the filling %'s!

So what I am saying is that adapting a something to a something is not always a gain unless you do the math and for that, you need to establish bench marks, for that you need to put study into practice... my opinion

 

Take the thought you are bringing into shape above, how will it draft not one but two fluids? Where will the drag and resulting friction (s) concentrate; how will the turns effect the consecrated/condensed transfer of air/fuel, where will it separate and pool...???

This is what I look at in ports, floors its a very big deal, next walls, how tall how wide where if any are the hidden narrows and how will they impact, then ceilings. Plenum is different, texture evap traps and the patterns when carborurated are again very important! Injection setups are a different set of equations but what I am seeing is folks are wanting to take parts of the different theories ignoring the properties that separate their behavior; as far as I know you just can't achieve better that way!

 

Lets take a quick look at your initial thought above.... Where we see straight flats what we'd likely prefer to see are soft flowing directional shapes (yes I know that complicates the cad) but its a one off so a pencil should do. You'll need to make a head port template which you'll pencil around in the cross sections which will prove/develop the flow shapes for modeling, it won't be easy but if you can't sketch it then how can you build it.

Next likely remove or delete the adapter thinking so, remove the down pipes and lower the intake right to the head ports incorporating a down angle instead; this will lower the body allowing you to design the plenum area above and. will also provide room for a buffering chamber for turbulent flows below the throttle plates! This will reduce greatly directional pressures to feed one side over the other directly related to throttle plate angles!

 

You cannot ignore velocity so you need to conciser head port shape final size, your will see thru sketching that the port runners will want to widen and narrow, take advantage of this, because it impacts flow and velocity, you will gain by growing your understanding of why this is so!

 

How much flow/volume @ what velocity will the head ports flow thru that qubic area, remember velocity is critical? Yamaha knows the what's and whys so to improve on the design you will need to establish those benchmark or its just hearsay!

If simplifying the fuel system delivery is the goal then that will likely come at some performance cost?

If performance is the goal then that will be found in flows and %s of fill and that gets costly! Believe me I know first hand...

 

There are many floor tricks that I haven't mentioned here nor have I suggested any head porting so, the heads stay stock and reversal down the road is easy to go back to the CV;)

Patch

 

Edit: I can't express how intricate a problem this can be and/or its impact on the apposing ports

will also provide room for a buffering chamber for turbulent flows below the throttle plates! This will reduce greatly directional pressures to feed one side over the other directly related to throttle plate angles!

Edited by Patch
Link to comment
Share on other sites

What about something similar to the OPs set up but with a longer inlet that turns into a collector at the top for a progressive 2brl. That might help with the turbulance and make kind of a velocity stack.

 

There was another attempt here a while ago. He claimed good results.

https://r.tapatalk.com/shareLink?url=https%3A%2F%2Fwww%2Eventurerider%2Eorg%2Fforum%2Fshowthread%2Ephp%3Ft%3D124413&share_tid=124413&share_fid=4890&share_type=t

 

A new twist on the single carb swap

 

Sent from my SM-G930V using Tapatalk

Link to comment
Share on other sites

What about something similar to the OPs set up but with a longer inlet that turns into a collector at the top for a progressive 2brl. That might help with the turbulance and make kind of a velocity stack.

 

There was another attempt here a while ago. He claimed good results.

https://r.tapatalk.com/shareLink?url=https%3A%2F%2Fwww%2Eventurerider%2Eorg%2Fforum%2Fshowthread%2Ephp%3Ft%3D124413&share_tid=124413&share_fid=4890&share_type=t

 

A new twist on the single carb swap

 

Sent from my SM-G930V using Tapatalk

 

If you would like to discuss the potentials, I suggest you look up our discussion on this topic. Unfortunately I can't remember the title of the thread? Maybe Puc or Flynfool does? Post there if you like after reading the give and takes we hash thru it.

You won't change my mind with regards to this type of adapter but I have thought thru some progressive carb linkages that could benefit power output.

Air flow is the heart to the engine, so you need 1st match what is there, then aim to improve on it.

You need to lower the setup.

 

I have commented on the setup you linked somewhere in a repost, not sure when that was, it is the same setup/adapter as what we see here.

Patch

Link to comment
Share on other sites

If you would like to discuss the potentials, I suggest you look up our discussion on this topic. Unfortunately I can't remember the title of the thread? Maybe Puc or Flynfool does? Post there if you like after reading the give and takes we hash thru it.

You won't change my mind with regards to this type of adapter but I have thought thru some progressive carb linkages that could benefit power output.

Air flow is the heart to the engine, so you need 1st match what is there, then aim to improve on it.

You need to lower the setup.

 

I have commented on the setup you linked somewhere in a repost, not sure when that was, it is the same setup/adapter as what we see here.

Patch

That's fine I'm just looking at rebuilding my carb rack for the second time in under five years diaphragm failing. If I can get the Single carb swap to perform that's a lot easier to work on then the rack of four.

 

Sent from my SM-G930V using Tapatalk

Link to comment
Share on other sites

That's fine I'm just looking at rebuilding my carb rack for the second time in under five years diaphragm failing. If I can get the Single carb swap to perform that's a lot easier to work on then the rack of four.

 

Sent from my SM-G930V using Tapatalk

 

Diaphragms should last longer than what you are experiencing. In any case though, rebuilding is not necessary to change the piston/slide diaphragms; simply remove the side covers and its all there in front of you!

Link to comment
Share on other sites

Diaphragms should last longer than what you are experiencing. In any case though, rebuilding is not necessary to change the piston/slide diaphragms; simply remove the side covers and its all there in front of you!
It wasn't starting and when I finaly got it to catch it would die if you didnt give it constant throttle. I pulled the slides out to cleen the needle jets and they are full of little holes. My best guess is something in the winter blend dost agree with them. I replaced them the end of the first winter of rideing and that was 4 years ago.

 

Sent from my SM-G930V using Tapatalk

Link to comment
Share on other sites

It wasn't starting and when I finaly got it to catch it would die if you didnt give it constant throttle. I pulled the slides out to cleen the needle jets and they are full of little holes. My best guess is something in the winter blend dost agree with them. I replaced them the end of the first winter of rideing and that was 4 years ago.

 

Sent from my SM-G930V using Tapatalk

 

If this is what you are experiencing at the moment as well then you should post the issue.

I'll split the problem by color..

 

This suggests a pilot jet issue.

This suggests a leaking at the needle so, opening the throttle compensates with more air added to the mix!

This represents a power issue not a start or idle issue

Bring this to a new thread and let us help..

Patch

Link to comment
Share on other sites

If this is what you are experiencing at the moment as well then you should post the issue.

I'll split the problem by color..

 

This suggests a pilot jet issue.

This suggests a leaking at the needle so, opening the throttle compensates with more air added to the mix!

This represents a power issue not a start or idle issue

Bring this to a new thread and let us help..

Patch

I actually just won a auction for a weber 32/36 so I am going to give it a shot. At worce what I payed I can still make my money back and ma e just waisted time tinkering. The bike is getting some much needed love right now so I will try it while I have everything apart.

 

Sent from my SM-G930V using Tapatalk

Link to comment
Share on other sites

I can't really see what #1 is but #2 looks to be a vacuum port where you would connect the vacuum advance. I don't remember what year bike you are working with, but the '83 boost sensor would connect there. Probably want to use a restrictor as that port looks to be about 3 times the diameter of the port on the stock carb.

Link to comment
Share on other sites

Venting the crank is best done at the manifold mounting plate as close to center as you can. You may run into accumulation problems with this design which would effect the valves; meaning a trap before the carb adapter is likely a good idea.

Vent the crankcase or it will make several vents on its own and each one will be a leak.

 

With port 2 you may use it for vacuum monitoring such as a permanent dash mounted gauged.

Patch

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...