Factory Pro Jet vs Dynojet Kit

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leevtr
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Joined: Sat Feb 11, 2012 9:16 pm
Location: Romford, Essex

Factory Pro Jet vs Dynojet Kit

Post by leevtr »

As above, whats the differences?? I had a dynojet kit fitted to my previous storm by my then mechanic, got it right first time with no issues whatsoever, and with good results when it eventually made it on the dyno. Lots of talk here about FPJ kits, yet most posts I've read about them , they always are not quite right and consantly need fettling??

What gives??

Bet I know who answers this first :lol:
" It was 2 minutes 5 minutes ago "
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VTRDark
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Joined: Sun Mar 18, 2012 9:24 pm

Re: Factory Pro Jet vs Dynojet Kit

Post by VTRDark »

OK if no one else is gonna answer then I will. :lol:

The biggest difference between them is the way the jet sizes are measured, the scale they use. Factory pro use the same sizing as Keihin so makes it relatively more simple to get tuned in as the sizes can be compared to the originals and one knows how much smaller or larger the jet is compared to originals. The hole I believe is a straight flush hole.

Dyno jets have their own scales/range. They are measured by flow rate and I believe the holes are tapered so the flow is forced through more like a venturi. So a 180 FP jet is a totally different size from a 180 Dyno jet, so be careful when someone says I got a 180 or whatever size jet unless you know the brand they are using.

Both companies use a totally different needle profile. Also the Dyno needles have 6 slots and the FP have 5.

With FP you just get the needle unless you by the race kit which requires other modifications similar to the dyno jet kits. Dyno jet needles are supposed to have a different diaphragm spring and they supply a drill bit to drill an extra lift hole in the slide. Saying that though, if you buy a UK kit they don't supply the springs. UK dyno kits supply X2 190 X2 180 X2 170 mains and a drill bit for the slide. US Dyno kits supply the above plus the springs and also supply X2 195 X2 185 and X2 175 main jets as well. I don't know why.

VTR's apparently run better without the extra lift hole drilled.

FP supply needles either alloy or Titanium depending on kit, a 172 180 182 185 188 mains X2 50 pilots and a packet of Allen bolts to replace the bolts in the float bowl.

But IMO jet kits are the biggest con going considering the price as you can just shim the original needles and buy Keihin jets for a fraction of the price. Shimming the needles will allow you to richen up the mixture but you can't go the other way and lean it out.

:wink:

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leevtr
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Location: Romford, Essex

Re: Factory Pro Jet vs Dynojet Kit

Post by leevtr »

That sorts that out then :confused :confused
" It was 2 minutes 5 minutes ago "
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scott02464
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Re: Factory Pro Jet vs Dynojet Kit

Post by scott02464 »

cybercarl wrote:OK if no one else is gonna answer then I will. :lol:

(:-})
Your the best man for answering this mate :lol:
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VTRDark
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Joined: Sun Mar 18, 2012 9:24 pm

Re: Factory Pro Jet vs Dynojet Kit

Post by VTRDark »

Maybe this will help http://vtr1000.org/phpBB3/viewtopic.php ... bs#p217047 :)
Your the best man for answering this mate
I don't know about that. :lol:

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