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 Post subject: Pod filters straight onto carbs
PostPosted: Fri Sep 08, 2017 7:03 pm 
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Joined: Mon Feb 25, 2008 11:44 am
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Location: Northern Ireland
Hi all
After several years, I'm at the final stages of completing my build; just the wiring and carbs to sort out (before disassembly for painting etc)

I'm looking for info on jetting; I have jolly moto pipes and pod filters straight onto the standard carbs. Otherwise standard motor, rebuilt with new pistons and cranks. I've searched a lot through the forum to get a starting point for jetting. Filters straight onto the carbs (Mad beaver etc) is quite controversial on here! The general consensus seems to be that this set up is very difficult to jet and will never work right, especially with standard carbs. But I like the look of it and it was always part of my plan. I'm not too worried about the bike being perfectly jetted so long as it goes reasonably well, I'm prepared to make compromises; I wont be racing this bike!

The best info I have so far was in a post from MC (matt) several years ago, who had a similar set up; "I raised the pilot jet one size larger and did run up to a 380/400 main jet but I think I ended up around 290/300 rears(uppers) & 280 fronts(lowers) I would need to drop the bowls to confirm those sizes thou .."

Can anyone who has run pod filters straight onto standard carbs give me a steer. I want something to get it running so I can get some miles on it before taking it to a dyno. If it feels reasonably good I may forego the dyno. I'm at sea level.

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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Sat Sep 09, 2017 10:37 am 
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Joined: Tue Nov 30, 2010 9:54 pm
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Location: Livermore, CA USA
I had the exact same set up except JL pipes. I had brand new Uni filters made. The only note I could find was changing from 250 main to 240. I usually keep very good notes on jetting but apparently haven't on this bike :???:

Subsequently I have swapped out the mad beaver set up for Bill Wilson's K&Ns.

Your mains sound too big for stock(ish) engine. Certainly won't hurt to start big and go down tho.

Good luck.

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1985 RZ500 (R6 suspension & body work)
(8) RZ350's
2006 R1 LE #158
Gold Wing/Trailer


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Sun Sep 10, 2017 6:33 pm 
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Joined: Mon Feb 25, 2008 11:44 am
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hi kpke
So you reckon I should be starting at about 250? What about the pilots?
many thanks


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Mon Sep 11, 2017 10:45 am 
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Joined: Tue Nov 30, 2010 9:54 pm
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Location: Livermore, CA USA
Yes. I went smaller from there. Feel free to start bigger if you wish.

Don't forget about elevation. I am at about 700 feet.

Unfortunately I have to use my memory on the pilots. I believe I left them alone. And the needles in the middle position.

I'll bet that I have handwritten notes on this. I never do jetting changes without documenting it, usually on my computer. :smt017

I'll try to remember to check my RZ500 note book this evening.

Good luck.

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1985 RZ500 (R6 suspension & body work)
(8) RZ350's
2006 R1 LE #158
Gold Wing/Trailer


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Mon Sep 11, 2017 3:54 pm 
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kpke wrote:

Don't forget about elevation. I am at about 700 feet.



I'm at sea level so would need to start on a larger size but not much different for 700 feet??


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Wed Sep 13, 2017 10:55 am 
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I looked through my notes and all I could find was a recommendation to use 27.5 or 30 pilots.

When I have a few minutes I will browse through my build thread and see if I have it noted in there.

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1985 RZ500 (R6 suspension & body work)
(8) RZ350's
2006 R1 LE #158
Gold Wing/Trailer


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Sun Dec 10, 2017 8:11 pm 
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kpke wrote:
I looked through my notes and all I could find was a recommendation to use 27.5 or 30 pilots.

When I have a few minutes I will browse through my build thread and see if I have it noted in there.


Hi kpke
Did you ever get a chance to check your jet sizes?

I'm ready to change the jets now so if you (or anyone) can give me some guidance on sizes that'd be great;
standard engine, jolly moto pipes, pod filters straight onto standard carbs. I'm at sea level in ireland.

many thanks to anyone who can help give me a starting point...


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 Post subject: Re: Pod filters straight onto carbs
PostPosted: Mon Dec 11, 2017 12:29 pm 
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Location: Livermore, CA USA
trix wrote:
kpke wrote:
I looked through my notes and all I could find was a recommendation to use 27.5 or 30 pilots.

When I have a few minutes I will browse through my build thread and see if I have it noted in there.


Hi kpke
Did you ever get a chance to check your jet sizes?

I'm ready to change the jets now so if you (or anyone) can give me some guidance on sizes that'd be great;
standard engine, jolly moto pipes, pod filters straight onto standard carbs. I'm at sea level in ireland.

many thanks to anyone who can help give me a starting point...


I just checked and could not find any mention of pilot jet size. Sorry. :smt009 Again, I am pretty sure I left the stock pilot jet in there.

_________________
1985 RZ500 (R6 suspension & body work)
(8) RZ350's
2006 R1 LE #158
Gold Wing/Trailer


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