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First test ride after the cam chain fiasco, and now what...it needs half choke to run...!

Surly a 1mm over bore and a porting job is not enough to require a needle move or jet change of this magnitude..

 

 

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First test ride after the cam chain fiasco, and now what...it needs half choke to run...!
Surly a 1mm over bore and a porting job is not enough to require a needle move or jet change of this magnitude..
 
 


+1 Agreed

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1 hour ago, mixxer said:

A cam off by one tooth would do it

OK here is a snap with the "T" lined up perfectly...not fun as it loves to roll off its mark...as a perfectionist I see that the lines on the cam gear are slightly skewed. But one more tooth looks extream...??

 

20170409_202012.jpg

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I turned my cam every which way today with a slotted cam chain gear. It seemingly made no difference. Point is that your issue may not be the cam. Choking the air flow with better results points to a fuel starvation, on your idle/pilot jet. 

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Question.... is this a custom cam... if so, is that a mark on the bottom of the cam shaft center? Is it not supposed to be in line with the can chain sprocket marks, or close? My mark lines up with the right side case line

Edited by 1gr8bldr

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30 minutes ago, 1gr8bldr said:

I turned my cam every which way today with a slotted cam chain gear. It seemingly made no difference. Point is that your issue may not be the cam. Choking the air flow with better results points to a fuel starvation, on your idle/pilot jet. 

I agree...too carb off and looked for any crud, debris or blokage...but I found none...fuel flows from the petcock sufficient to run a small bock chevy...

I did not touch air screw. Idle jet is a 45 and main is a 122..all worked well before tensioner failed....

But it acting just like fuel starvation...

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37 minutes ago, 1gr8bldr said:

Question.... is this a custom cam... if so, is that a mark on the bottom of the cam shaft center? Is it not supposed to be in line with the can chain sprocket marks, or close? My mark lines up with the right side case line

Yes...it's a webb cam 89a.... I did not remove the sprocket from the cam so it's in the same position as when all was well....

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Get some fine strand electrical wire, strip out a couple of strands and twist them together and use that to clean your jets, don't force it in there in case a bit breaks off, make it so they travel easily through with some carby cleaner..

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Yep, a clogged pilot circuit/jet Is a likely problem.  How long did the carb sit during the rebuild?  It could also be an air leak at the manifooled.

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Yep! Grab a spray bottle with some water in in and spray at the intake manifold wile it's running, it make a difference when you spray you know where to look.

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ok im getting convinced that my modifications have increased the fuel needs.

intake boot is not leaking, cam looks to be installed correctly, no vacuum blocking of the tank, all ports that I can blast carb cleaner through seem to be open...

so my question is this...anybody out there in 230 land that have ported the head, have you seen the need to increase jets and if so by what percentage.

also is there a source for buying jets in kit form (I would like to buy multiple sizes of both jets so I can play around and get what works best...

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14 minutes ago, daled said:

also is there a source for buying jets in kit form (I would like to buy multiple sizes of both jets so I can play around and get what works best...

https://www.denniskirk.com/dg/genuine-keihin-13-series-main-jets-34-1200.p170048.prd/170048.sku

Edited by VortecCPI

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On 4/9/2017 at 7:28 PM, daled said:

First test ride after the cam chain fiasco, and now what...it needs half choke to run...!

Surly a 1mm over bore and a porting job is not enough to require a needle move or jet change of this magnitude..

A larger bore (displacement) INCREASES signal at the carb so no way.

A wild cam will decrease signal at low engine speeds.

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13 minutes ago, daled said:

, all ports that I can blast carb cleaner through seem to be open...

Are you getting fluid through the fuel screw passage?  With the screw out, not just into the Venturi but also through the side inlet into  where fuel is picked up from the float bowl.

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1 hour ago, daled said:

ok im getting convinced that my modifications have increased the fuel needs.

intake boot is not leaking, cam looks to be installed correctly, no vacuum blocking of the tank, all ports that I can blast carb cleaner through seem to be open...

so my question is this...anybody out there in 230 land that have ported the head, have you seen the need to increase jets and if so by what percentage.

also is there a source for buying jets in kit form (I would like to buy multiple sizes of both jets so I can play around and get what works best...

Usually the increase in vacuum will suck more fuel through the same jet. I had to prove it. I assumed my build would require bigger jets but later with the AFR meter found out otherwise. My stock bike took 120 and the built  bike 122. LOL, I even tried all jets up to 138

Edited by 1gr8bldr
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