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Author Topic: Carb Alignment with Big Bore Cylinder  (Read 450 times)

Offline DOUGLAS

Carb Alignment with Big Bore Cylinder
« on: August 13, 2018, 07:05:15 PM »
was able to get some time on my bike today. having a big bore cylinder in a OEM frame I did not like my options with the alignment of the carb to the intake. the top of the carb hits the frame making it extremely difficult to install and to service the carb. trying stock OEM cr250 and UPC intakes the out come was all the same poor alignment. I picked up an aluminum billet one from atvguy and this was the closest one but still did not like the way it fit. I mocked up an intake. time to send it out to fab shop.

« Last Edit: August 16, 2018, 05:27:54 PM by Tbone07 »
LED 363 87 stock frame

Offline hickwheeler

Re: CARB ALIGNMENT
« Reply #1 on: August 13, 2018, 07:09:38 PM »
I'm not having those alignment issues. I'll get you a pick to night
88 330 worked over by Pete
88 ct350pv (BOF Build)
89 440 Packard built pilot  (Sold)

Offline DOUGLAS

Re: CARB ALIGNMENT
« Reply #2 on: August 13, 2018, 07:55:22 PM »
do you have a 350 esr cylinder in a stock frame running an led intake ?
LED 363 87 stock frame

Offline DOUGLAS

Re: CARB ALIGNMENT
« Reply #3 on: August 13, 2018, 07:56:14 PM »
and 1/4 spacer plate ?
LED 363 87 stock frame

Offline hickwheeler

Re: CARB ALIGNMENT
« Reply #4 on: August 13, 2018, 08:13:27 PM »
I have pro cross cylinder vf2 reeds with a stretch stock intake and a stock air intake with JL airbox eliminator
88 330 worked over by Pete
88 ct350pv (BOF Build)
89 440 Packard built pilot  (Sold)

Offline havinnoj

Re: CARB ALIGNMENT
« Reply #5 on: August 14, 2018, 01:26:25 AM »
Glad you got it sorted Doug. Out of curiosity, did you have any issues without the spacer?

Offline DOUGLAS

Re: CARB ALIGNMENT
« Reply #6 on: August 14, 2018, 05:52:38 AM »
without the spacer the alignment is still not good but useable. the spacer keeps the petals from touching the cylinder causing premature wearing. using the spacer throughs the alignment out more. as you can see in the pics. using different intakes does not clear this up on a stock frame. changing the angle pitching it down to a 30 degree is the best option for me. it also gives room at the top of the carb to remove the top to change cable and service carb.  i'm sending out my draft to the fab shop this week. 
LED 363 87 stock frame

Online jcs003

Re: CARB ALIGNMENT
« Reply #7 on: August 14, 2018, 10:49:54 AM »
short body carb, or a 35mm carb bored out.  just a thought.

Offline havinnoj

Re: CARB ALIGNMENT
« Reply #8 on: August 14, 2018, 11:46:32 AM »
Wow, that's pretty extreme, didn't know the ESR cylinder intake angle was that changed from some of the others.

Offline DOUGLAS

Re: CARB ALIGNMENT
« Reply #9 on: August 14, 2018, 11:58:11 AM »
short body carb, or a 35mm carb bored out.  just a thought.
I already have a 38 that Arlen suggested to run. he built the motor so i'm going to follow his advice. I did think of also getting a short body.  I also had it polished. waiting for its return from Race Reflections. thanks for your thoughts on this.
LED 363 87 stock frame

Online jcs003

Re: CARB ALIGNMENT
« Reply #10 on: August 14, 2018, 12:07:17 PM »
just to clarify.  a 35mm has is smaller altogether and should rectify your fitment issues.  If it is then bored, it will compensate for the lack of flow you need with the big bore.

Offline F-Red

Re: CARB ALIGNMENT
« Reply #11 on: August 14, 2018, 12:41:24 PM »
UPC intakes the out come was all the same poor alignment.

Doug,

That is some serious misalignment.  :o I have the same cylinder and carb. I'm running ESR's intake with a UPP manifold. Mine was a little tight, nothing like yours.

What is a UPC intake? Typo?

Want To See My Wieners?

Online 2Nubs

Re: CARB ALIGNMENT
« Reply #12 on: August 14, 2018, 01:51:12 PM »
My boot between the carb and filter lightly rubs the frame, but I don't have the carb interference you have.

I also have an ESR cylinder and 39mm PWK using a factory intake. Curious of what the variable is here.
86 330

Offline DOUGLAS

Re: CARB ALIGNMENT
« Reply #13 on: August 14, 2018, 01:57:35 PM »
UPC intakes the out come was all the same poor alignment.

Doug,

That is some serious misalignment.  :o I have the same cylinder and carb. I'm running ESR's intake with a UPP manifold. Mine was a little tight, nothing like yours.

What is a UPC intake? Typo?


  yup its UPP typo.
LED 363 87 stock frame

Offline Hawaiiysr

Re: CARB ALIGNMENT
« Reply #14 on: August 14, 2018, 02:17:15 PM »
i have the same issues with a stock frame, stock cylinder, cr manifold, AS 38mm and a eliminator. i think a upp will fix my issues but i also want to install a JL bracket. i still have to play around with it all. not enough time in a day