|
|
Post by jareeb on Apr 29, 2015 11:23:31 GMT -5
anyone have any experience with these carbs? none of my dell jets work with this carb. trying to figure out if they usually like bigger jets than the dells or if they like smaller ones because the "save fuel." the carb is a 21mm where my dell was just a 19mm.
dell had a 40 idle and a 115mj and it ran okay with those.
the cp came with a 40 idle and a 100mj. doesnt idle and rattles at wot. so i know they need to be bigger. how big im not really sure.
|
|
|
|
Post by humanshield on Apr 29, 2015 11:42:26 GMT -5
If your engine can handle the extra air, the main result of going to a larger venturi carburetor is that the pressure drop in the venturi will be less do to the increased size of the venturi.
So, you may need to adjust the float bowl settings in the cp so that the level is slightly higher to compensate. Raising the float level decreases the vacuum required to pull fuel through the jets.
That could help with the idle and main jet.
But I also think you will need at least a 115 main jet since that worked with engine before. You may have to go larger (or smaller). It's gonna take some experimenting. Just dont run it lean.
|
|
|
|
Post by jareeb on Apr 29, 2015 11:50:07 GMT -5
|
|
|
|
Post by humanshield on Apr 29, 2015 12:55:28 GMT -5
why dont they make a 110-128? It's better for THEM if you have to buy BOTH sets ? Well, if it was rattling at WOT with a 100 jet....I'd go with the 120 - 138 set only because it's better to run rich than "poor" But your dilemma will be that if it runs too rich, it still wont run as good as it could. On the other hand, if you get the 100 - 118 kit, you "could" potentially drill out one of them. Heck, for that matter, check into drilling out the one you have to 115 then 118. Just a thought |
|
|
|
Post by 190mech on Apr 29, 2015 14:18:12 GMT -5
|
|
|
|
Post by fe53series3 on Apr 29, 2015 14:39:58 GMT -5
anyone have any experience with these carbs? none of my dell jets work with this carb. trying to figure out if they usually like bigger jets than the dells or if they like smaller ones because the "save fuel." the carb is a 21mm where my dell was just a 19mm. dell had a 40 idle and a 115mj and it ran okay with those. the cp came with a 40 idle and a 100mj. doesnt idle and rattles at wot. so i know they need to be bigger. how big im not really sure. Check out this document...... it is mission critical to your project: www.polini.com/dep/polini_ric_carburat.pdfYou can see that the Polini and dellorto jets are interchangeable, once you know the thread diameter. I wonder if the needles are the same as the W series? Either way..... you really should know what needle you've got in now. That linked doc also has all the Polini needle specifications..... so if you know your needle number, then we can check its specs and understand what it is doing. I would anyway go for the 100 - 120 range...... if you go bigger, you might not even be able to do any testing. For idle..... have you tuned the fuel/air idle circuit? |
|
|
|
Post by jareeb on Apr 29, 2015 17:56:22 GMT -5
None of my Dell jets work. Koso interchange with cp carb
|
|
|
|
Post by fe53series3 on Apr 29, 2015 18:21:59 GMT -5
None of my Dell jets work. Koso interchange with cp carb That's tough..... that doc seemed to indicate they were interchangeable. Ah well..... I'd still go for the 100 - 120 range, and also get the needle number. |
|
|
|
Post by 190mech on Apr 29, 2015 18:26:44 GMT -5
None of my Dell jets work. Koso interchange with cp carb Koso is a Keihin PWK knock off,so jetting should be dirt cheap! |
|
|
|
Post by niz76 on Apr 29, 2015 19:12:02 GMT -5
Let us know what you think Jareeb! I've been eyeballing that Polini Cp 21 also...
|
|
|
|
Post by jareeb on Apr 29, 2015 21:39:26 GMT -5
Thanks for all the input. ill be just ordering the polini jets. And yes niz ill let you know.
|
|
|
|
Post by vlatx on May 2, 2015 10:48:30 GMT -5
The polini CP 21mm Getto Massimo 100 - Main Jet 100 Getto Minimo 40 - Low Jet 40 Spillo 14/22 - Needle 14/22 Valvola 24x30 - Valve 24x30 Bussola Polverizzatore d.2,7 - Atomizer Bush d.2,7 In the case where the carburetor is mounted on racing engines that exceed 12000 rev / minute, read the following directions. The carburetor Polini CP is lighter than other carbs in trade and in certain conditions may cause problems of emulsion fuel. Air bubbles are sucked into the jet is giving very serious engine problems that become poor although perhaps a large jet or right; the engine begins to detonate until failure. First check the installation instructions in the "Adjustments" to make sure the carburetor Polini CP has been tested on the model of your bike or scooter by technicians Polini and follow the signs. If in the "Adjustments" your model of motorcycle or scooter It is listed as follows: Assemble the sight bowl (cod.343.0029) that will allow you to detect the problem and if necessary to soften the rubber collector until the problem disappears. If the problem persists, increase the mass of the carburetor mounting flange coupling filter iron (cod.343.0028) produced by POLINI. Once you solved the problem replace the standard tray.  |
|
