Author Topic: PD42B pumper carbs  (Read 860 times)

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Offline Don R

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PD42B pumper carbs
« on: January 28, 2019, 05:56:03 pm »
 Do they serve any useful purpose besides being correct for an F2?  I grabbed a pretty nice set at Davenport last year just because they were priced right. Most mentions of them seem to lead me to believe they are no better than equal to a round top. Since I had no performance carbs I considered putting them on an 836.
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If you love it, set it free, if it stays it's probably one of my 750's.
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Offline KayOne

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Re: PD42B pumper carbs
« Reply #1 on: January 28, 2019, 09:03:33 pm »
I run them on my 836 K1, like the jump they give with the accelerator pump. Don’t think they have more  power up top though.
CB750 K1 restored
1979 CB750Fz - original except for exhaust, 14000km
1984 VF45F Interceptor - all original, 12000 km
1968 S90 - all original, 2100 miles
1973 H2a, Restored
1973 H1D, next project
CB750K1 (sold)
1976 KZ900 (sold)
1981 CB900F (under restoration)
2015 Yamaha FJ09, my appliance rider

Offline Don R

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Re: PD42B pumper carbs
« Reply #2 on: January 28, 2019, 10:03:12 pm »
 I'll probably put them on the drag bike engine with the pod filters I took off a kz1000 I bought. It doesn't run yet anyway and would look better than the round tops with no filters. I have some 130 mains and 42 pilot jets to try and the pods are baffled inside for when it is running again.
No matter how many times you paint over a shadow, it's still there.
If you love it, set it free, if it stays it's probably one of my 750's.
 CEO at the no kill motorcycle shop.

Offline seanbarney41

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Re: PD42B pumper carbs
« Reply #3 on: January 29, 2019, 03:19:27 am »
I have a set that I spent serious money to have rebuilt by harisuluv.  They still have been a failure.  I think it is pretty hard to get the short boots they require to seal.  So of course, they are not gonna work with leaky boots.  I gave up and put round tops on my f2 resulting in the fastest stock displacement bike I have ridden, out of dozens.
If it works good, it looks good...

Offline Don R

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Re: PD42B pumper carbs
« Reply #4 on: January 29, 2019, 08:52:47 am »
 Cool beans, I'm only out  $20. The guy that had them at the swap meet didn't know what they fit, I said for $20 I'd take a chance. I have another set on a 77K that were rebuilt a couple years ago. They were left sitting with unknown fuel in them when my brother took that bike home. 
No matter how many times you paint over a shadow, it's still there.
If you love it, set it free, if it stays it's probably one of my 750's.
 CEO at the no kill motorcycle shop.

Offline turboguzzi

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Re: PD42B pumper carbs
« Reply #5 on: January 29, 2019, 03:21:06 pm »
i dont have direct experience with these but with something similar off a kawasaki. these later carbs just before CV era were more drive-ability/emissions oriented. Pull the slides up and youll see the opening is oval shaped, considerably less area than their full claimed diameter. add to this the choke plates  restriction and reach your own conclusions... but for 20$ i'd grab them too. they would sell for a 100 in swap meets here