Author Topic: Ongoing PD46 carburettor woes (possibly)  (Read 4499 times)

Offline JezzaPeach

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #30 on: June 15, 2020, 08:50:48 AM »
PS another thought. I think the idle screws may have small holes in them that may get blocked. Not sure but worth checking.
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from 1975-78. Garnet Brown.

Online K2-K6

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #31 on: June 15, 2020, 09:50:59 AM »
"David Silver has repro ones at a more palatable £30 + VAT for the coils although they don't seem to be handed (same one for both the left and the right side as far as I can see) - has anyone had experience of these?"

No direct experience of these but they don't appear to draw any significant level of failure comments on here.

They would most likely give you a competant fix immediately though to allow you riding it while running well. 

The originals worth keeping for if you decide to repair/ or for someone else to do the same if they wanted originals.

Offline JezzaPeach

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #32 on: June 15, 2020, 01:55:45 PM »
Yes the DSS ones worked very well for me and fitted fine.
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

Offline keithtraffic

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #33 on: June 15, 2020, 07:04:02 PM »
Thanks - did you replace the plug caps as well - the DSS ones don't come with those?

Offline JezzaPeach

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #34 on: June 16, 2020, 04:02:56 PM »
Yes the plugs NGK D7EA and NGK resistor caps. 2 long and 2 short with angles at top in black. I’ll try to attach pics. Didn’t cut cables short and outer plugs can point back and in with leads through p clips. Will try a pic of that too
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

Offline deltarider

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #35 on: June 16, 2020, 07:10:06 PM »
I prefer 2 long straight on the inner cylinders, far less chance of the HT cable touching the exhaust and it gets them out of the water spray from the front wheel better IMO
Me too. Also I don't like HT leads direct contacting the head. Better to insulate real well!

Online K2-K6

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #36 on: June 16, 2020, 07:14:13 PM »
Don't know if anyone is doing the same,  but I assemble the leads into plug caps using silicone grease which improves water resistance and helps as you screw the cap in.

It's high temperature resistant and I just by it in little tubs from plumbing supply shop.

Edit;- https://www.cityplumbing.co.uk/Polypipe-Silicone-Grease-100g-SG100/p/919370 it's this one I use.
« Last Edit: June 16, 2020, 07:17:15 PM by K2-K6 »

Offline JezzaPeach

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #37 on: June 16, 2020, 08:21:54 PM »
Good points. I’ll make sure the leads turn up a bit more.
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

Offline JezzaPeach

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #38 on: June 16, 2020, 08:29:58 PM »
Actually just checked a despite the pic 2&3 are well clear, but the long straight ones were the original format (?) so good to keep original look (apart from the pressed metal caps maybe!)
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

Offline keithtraffic

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #39 on: June 27, 2020, 05:33:26 PM »
Hi All,

So......

I have replaced the coils (with aftermarket ones for DS) as well as the plug caps (just for good measure as the ones fitted actually look pretty good) and unfortunately things have not improved - same poor low revs performance from cylinder 1 and the slight 'sputting' backfire ae low revs is still noticeable.

It's looking like I am going to have to remove the carbs again to make absolutely sure everything is totally clear and clean - but does anyone have any final last thoughts where else to look before I do down this route - it seems most other things have been tried!

Also does anyone have a decent rubber connector between Carb 1 and the air box - I have noticed mine is beginning to split and an not sure it will survive another carb change (but its not the source of any problems as I have made sure its not leaking when testing the tickover!)

Offline Bryanj

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #40 on: June 27, 2020, 07:19:19 PM »
I think that is the especially unique one due to length and shape, it was discussed on the forum elswhere about a member on US site hand making them

Offline OZZYSBIKES

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #41 on: June 30, 2020, 06:38:37 AM »
Re the carb to inlet box rubbers, I managed to get in touch via the us forum and email with the man who is manufacturing replacements, he is very helpful, I got mine delivered in about a week and less than $50 including postage, I'll get his email when I finish work,

PS I am having very similar problems with my bike, I am about to clean the pilot jets for the fourth time which does get the bike running ok for a while, I am on the lookout for a set of alternative carbs as these PD carbs seem prone to issues (odd as they are not particularly complex carbs)

Offline Bryanj

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #42 on: June 30, 2020, 07:08:58 AM »
Problem was then were designed to run as lean as possible for california so any blockage at all makes them impossible

Offline OZZYSBIKES

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #43 on: July 01, 2020, 06:27:45 AM »
Let me know if or when they are for sale, if I can have first refusal it will be appreciated

Offline OZZYSBIKES

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Re: Ongoing PD46 carburettor woes (possibly)
« Reply #44 on: July 01, 2020, 06:33:22 AM »
The email address for Paul Gabor is mybluebike2004@yahoo.com

He responds quickly and is a pleasure to deal with, the rubbers that you will receive are not quite as good looking as genuine ones but not noticeable when fitted, not much choice anyway, the ones from Germany on Ebay are twice the cost and I believe are from Paul

 

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