32mm Polini PWK Carburetor experiment

  • Looks like your missing a bolt from the crank cases near inlet though.

  • @NINJA possible but I don't see a blanked out airbox causing issues, just a smooth run through a new filter.

    Yeah that top bolt is missing, its been like that since the previous owner rebuilt it, I've got a bolt kit on order which hasn't arrived yet but I'm certain it doesn't leak, tried spraying isopropyl on it while revving etc in past

  • @Glynn123 OK as you've increased the airflow with the larger carb, then I would look at the other 2 elements aka fuel and spark. If there is sufficient fuel reaching the carb & barrel with no blockages, then perhaps a different plug may help? What's your current plug like and have you performed a plug chop since you installed the carb? Maybe doing that will give you some clues in which direction you need to go???

  • @NINJA I'll try a different plug and maybe go for a regular 15 minute run with varied rpm tomorrow to get a baseline, hadn't tried a new plug yet but bought a set of four BR8ES to play around with, I'm thinking of dropping the needle again to test but its a ballache with the split cables etc haha

  • @Glynn123 I'd look at your plug first before changing any of the jets etc. As the colour of your plug will indicate which direction you need to go in. Maybe even try a colder grade plug or an Iridium one and see what occurs with those???

  • @NINJA been running it on an iridium for a while now, bought the standards just for plug chopping

  • @Glynn123 Good idea!!! :thumbs_up_medium-light_skin_tone:

  • Finally getting somewhere with this carburetor, sorry for the wait, had a little incident with buying a car I definitely shouldn't of bought haha.
    Was having severe spluttering with the DT all the way to main jet, the bike would literally barely run under load unless you were flat out. Narrowed this down to the needle and invested in a polini needle kit. Currently running a 140 main and 42 pilot, along with the standard N68E needle. The bike actually fouled it's plug after trying to startup again after a 5 mile ride, it was running allot worse in the 15 degrees weather we had compared to when I last played with it in around 5 degrees weather. I tried the leaner JJK needle and found it was bogging on big throttle inputs, so raised it a notch to find the bike had transformed. I just went a short 10 mile ride and the bike is a totally new beast, miles better than standard carb, loads of torque from idle. The only issue I'm finding now is a splutter at low throttle say 1/8th under, so I'm guessing the pilot is rich. However upon checking the new plug I fitted the bikes running abit lean, so tonight I fitted a JJN needle, which from what I can gather will give a leaner low end with richer mid and top, I've left it in the mid position for now. Once this weather clears up Abit and I'm back off work I'll give the bike another shot and post an update, but I'm finally glad to be getting somewhere with this bike, as it was proving a minefield a while ago.

  • @Glynn123
    Be careful of the float level, the angle of the inlet isn't suited for most carbs. It's a real pain in the ass to setup.
    I ran a Mikuni TM32 with a WR200 Inlet manifold and it was good but always had trouble with float control.

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    The Mikuni TMss with angled venturi design just works for me.

    The WR200 had a TM30ss, I've used a TM34ss from a Suzuki RGV 250 VJ22, which worked well,


  • @Darty ah right cheers, I've had no issues so far on the standard float height the carb came with, what symptoms should I be looking for? Just a bog when holding bike wot for a while? Had bike flat out for a good minute or so in 6th and never seen any issues?