The Varastorm Dyno run

Just post charts and set up details.
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Stephan
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Re: The Varastorm Dyno run

Post by Stephan » Fri Feb 27, 2015 10:55 am

Try to put back paper filter at first.

Bigger number of jet, more fuel. To be sure whether pilot jet is lean or rich, try to 1/2 turn out and see what happen.

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Varastorm
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Re: The Varastorm Dyno run

Post by Varastorm » Fri Feb 27, 2015 11:08 am

Stephan wrote:Try to put back paper filter at first. Bigger number of jet, more fuel. To be sure whether pilot jet is lean or rich, try to 1/2 turn out and see what happen.
Hi Stephan, Thanks for the reply.

I am with you on the bigger the number the more fuel idea, but does this mean the same for the air pilot jet?

I have to strip the fairing, tank, clock & seat plastics down before I can access the air box :roll: So I try to have a plan & change as much as I can whilst in there, only small changes though & hopefully for the better :lol:

It takes 2 hours to adjust the pilot screws...
PS. "The greatest obstacle to discovery is not ignorance, but the illusion of knowledge."

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lloydie
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Re: The Varastorm Dyno run

Post by lloydie » Fri Feb 27, 2015 11:25 am

No air screw on these only fuel screw .



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Stephan
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Re: The Varastorm Dyno run

Post by Stephan » Fri Feb 27, 2015 11:44 am

It would be good to get tool for adjusting the fuel screw, not sure if access is the same as VTR has. Somebody here can post details, I know at least 3 people around me having this tool, so never needed to get one for me.

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VTRDark
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Re: The Varastorm Dyno run

Post by VTRDark » Fri Feb 27, 2015 11:45 am

You keep saying air pilot jet which is confusing. You have the air bleeds which are the brass tubes you can see on top of the carbs by the stacks. Fuel pilot jet and fuel mixture screw is what we are dealing with here. And yes in theory going larger increases the amount of fuel flow but when you start adding more air which you have done with the filter or you try going with an open airbox or FIL mod then things can change dramatically as more airflow also draws/pulls more fuel through. I don't know where this turning point is but it certainly confuses things. It's usually on the mains where the fuel increase is hence the reason for smaller mains with the bellmouth v stacks. I blame Bernoulli, it's all his fault :lol: I think when one starts adding masses of air like that then more control over the air bleeds on top is required.

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Varastorm
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Re: The Varastorm Dyno run

Post by Varastorm » Fri Feb 27, 2015 12:12 pm

cybercarl wrote:You keep saying air pilot jet which is confusing.
Oops, sorry. I know what I mean but using the wrong terminology... my apologies.

I might of been confusing myself by looking at air pilot jet too, I think we are all confused :lol: :lol: :lol: Even my dog :lol:

Bike is stripped & I am going to try front 1 1/4 out rear 1 1/2 on the fuel screws :wink:

Thanks for the input & helping out a very confused guy & dog :lol: :thumbup:
PS. "The greatest obstacle to discovery is not ignorance, but the illusion of knowledge."

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Varastorm
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Re: The Varastorm Dyno run

Post by Varastorm » Fri Feb 27, 2015 1:36 pm

Change of heart,

I am going to put the Std Varadero jets in the VTR carbs.

Looking at the dyno fuel & air ratio its way too rich.

Anyone know how much a change in main jet size makes on the F&A ratio? Say from a 175 to a 178?

Mains #168 front.
Mains #170 rear.

#42 pilot jet, fuel screw.

1 1/2 out front 1 3/4 out rear pilot (Fuel screw)

If its poor, I'll change it again. At least We will know if it works or is a waste of time :thumbup:
PS. "The greatest obstacle to discovery is not ignorance, but the illusion of knowledge."

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VTRDark
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Re: The Varastorm Dyno run

Post by VTRDark » Fri Feb 27, 2015 2:50 pm

IIRC I read somewhere that 2 to 3 jet sizes will move up or down one on the scale but how true that is I don't know. But it's not as simple as that because you need to take into consideration needle height, air pressure, temperature etc which is all going to have an affect on this.

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Varastorm
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Re: The Varastorm Dyno run

Post by Varastorm » Fri Feb 27, 2015 3:05 pm

cybercarl wrote:IIRC I read somewhere that 2 to 3 jet sizes will move up or down one on the scale but how true that is I don't know. But it's not as simple as that because you need to take into consideration needle height, air pressure, temperature etc which is all going to have an affect on this.
Thanks Carl, appreciate that.

I just cracked her up again & she sounds sweet & very crisp to throttle inputs but..

It now hangs @1100rpm slightly before returning to idle @1000rpm for a second before dropping to 900rpm then back up to idle @1000rpm. This all happens in about 3 seconds.. I suppose no one would notice in the real world :roll: :lol:

When brining it up to temp & the throttle is blipped, it sometimes spit's back through the carbs, not often but it has done it.

This is only whilst warming up though. I was going to take it for a spin but it's far too cold & windy now.

It looks as if I am going to have strip it again, & see if screwing the pilots out 2 1/2 front 2 3/4 rear will help. If not its back up to #45's on the pilots.

Thanks :thumbup:
PS. "The greatest obstacle to discovery is not ignorance, but the illusion of knowledge."

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