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Offline Jerry Rxman Griffin aka MuthaF'er

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Installing New Style CR Carbs - NEW questions 5/28
« on: May 22, 2012, 05:12:00 PM »
I'm fitting the CR's and could use a little expertise from those of you that have been there before me  ;D

Fuel line stuff - there's been much debate/info about fuel line sizes with the CR carbs. Our stock fuel line size is 5.5mm while the carb inlet is ~ 6.5mm. Guys have been trying to find adapters, etc. I just returned from my Honda shop with some new soft 5.5mm hose. Guys, this 5.5mm goes onto the carb inlet just fine, no adapter necessary. Don't beat youself up over this!It is a very tight fit but it works. I hung the end of my 5.5mm line over my shop light bulb and heated it so that it would stretch over the inlet. A little heat, a little twisting and pushing - viola, it's on. Fits good.  Now, what I'd like to pick the brain trust about is all the inlets. Again, more debate/info. There are inlets between pairs of carbs with the center one open and ready to acept my 5.5mm fuel line so I went with a single line for my single line petcock and left the other 2 alone. SO, pray tell, what is that fuel line looking fitting on the outside of #1 below the choke lever?? Does it need to be tubed or left alone as is? Plugged perhaps? End of my fuel line stuff  ;)

On to throttle cables......  I'd really love to make my stock 75/76 CB750F cables work! Has anyone managed to make this happen? I've learned through the search function and playing that it is imperative to install both cables prior to installing carbs. VERY understandable. However the search function yields differing results. I need to take the carbs off from my test fit to install the 1/8" brass sync ports and HOPE to only have to put them back on one time! I know you're saying "yeah right, good FN luck!". PLEASE help me make this happen.

Thanks to all contributors  :)

 
« Last Edit: May 28, 2012, 09:56:17 PM by Jerry Rxman Griffin »
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Offline MRieck

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Re: Installing New Style CR Carbs - Couple questions
« Reply #1 on: May 22, 2012, 06:09:18 PM »
Quote from: Jerry Rxman Griffin on May 22, 2012, 05:12:00 PM
I'm fitting the CR's and could use a little expertise from those of you that have been there before me  ;D

Fuel line stuff - there's been much debate/info about fuel line sizes with the CR carbs. Our stock fuel line size is 5.5mm while the carb inlet is ~ 6.5mm. Guys have been trying to find adapters, etc. I just returned from my Honda shop with some new soft 5.5mm hose. Guys, this 5.5mm goes onto the carb inlet just fine, no adapter necessary. Don't beat youself up over this!It is a very tight fit but it works. I hung the end of my 5.5mm line over my shop light bulb and heated it so that it would stretch over the inlet. A little heat, a little twisting and pushing - viola, it's on. Fits good.  Now, what I'd like to pick the brain trust about is all the inlets. Again, more debate/info. There are inlets between pairs of carbs with the center one open and ready to acept my 5.5mm fuel line so I went with a single line for my single line petcock and left the other 2 alone. SO, pray tell, what is that fuel line looking fitting on the outside of #1 below the choke lever?? Does it need to be tubed or left alone as is? Plugged perhaps? End of my fuel line stuff  ;)

On to throttle cables......  [b]I'd really love to make my stock 75/76 CB750F cables work![/b] Has anyone managed to make this happen? I've learned through the search function and playing that it is imperative to install both cables prior to installing carbs. VERY understandable. However the search function yields differing results. I need to take the carbs off from my test fit to install the 1/8" brass sync ports and HOPE to only have to put them back on one time! I know you're saying "yeah right, good FN luck!". PLEASE help me make this happen.

Thanks to all contributors  :)
They will work Jerry.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - Couple questions
« Reply #2 on: May 22, 2012, 10:38:13 PM »
Thanks Mike!

Any answers about the fuel line looking fitting below the choke lever anyone?
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Offline lordmoonpie

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Re: Installing New Style CR Carbs - Couple questions
« Reply #3 on: May 23, 2012, 09:10:57 AM »
Got any pics to help Jerry?
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Offline MRieck

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Re: Installing New Style CR Carbs - Couple questions
« Reply #4 on: May 23, 2012, 09:30:26 AM »
Jerry...that piece you are talking about is part of the cold fuel enrichment circuit (choke). It allows air in when the lever is pulled up to pull fuel out of the bowl. Consequently it allows crap in there which can have a negative effect on the plunger seal.  ::)The very small (in physical size) jet is screwed into the bowl. It is far to large and cause more problems than it solves
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - Couple questions
« Reply #5 on: May 23, 2012, 06:33:34 PM »
LMP, thanks for checking in! Michael came through again. That's what I was trying to find out.
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Offline MRieck

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Re: Installing New Style CR Carbs - Couple questions
« Reply #6 on: May 23, 2012, 08:12:36 PM »
Quote from: Jerry Rxman Griffin on May 23, 2012, 06:33:34 PM
LMP, thanks for checking in! Michael came through again. That's what I was trying to find out.
I'm going to have drinks with you some day....you know that Jerry.....right? ;D ;D
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - Couple questions
« Reply #7 on: May 23, 2012, 08:16:31 PM »
Yeah, and it will cost me BIG time for what I owe you!
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Offline brandEn

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Re: Installing New Style CR Carbs - Couple questions
« Reply #8 on: May 23, 2012, 09:04:59 PM »
Jerry you should invest in the smallest starter jets they sell. If you remove the float bowl they are the brass jets in the bottom. Even the smallest they sell are to big but its better than what they come with.

get these
part number #019-370
#35 starter jet

they come with #45 installed.

The CR29's are great once they are setup for the street. But the biggest downfall IMO is buying the spendy parts to get them that way. They are racing carbs after all....
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Offline Retro Rocket

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Re: Installing New Style CR Carbs - Couple questions
« Reply #9 on: May 23, 2012, 10:19:09 PM »
Jerry's using CR31's Branden, more reason to use the smaller starter jets...
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Offline brandEn

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Re: Installing New Style CR Carbs - Couple questions
« Reply #10 on: May 23, 2012, 10:31:41 PM »
Quote from: Retro Rocket on May 23, 2012, 10:19:09 PM
Jerry's using CR31's Branden, more reason to use the smaller starter jets...

Oh wow,. I assumed they were 29's but you know what they say about assUme...lol
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - Couple questions
« Reply #11 on: May 23, 2012, 10:43:13 PM »
Yeah, 31's.

I have spares - 115 & 125 and 62's (!?!?). Guess I should take a bowl off, huh before installing?! I have Mike's Stage 4 head job with the 34mm intakes to go along with the 900 and Megacycle 125-75. How's that compare to your jetting recommendation?

My brass sync fittings are supposed to show up tomorrow but I'm running out of my week. Working Friday then GZv2.0 Sat & Sun. Gotta install those and try to get my stock cables to work. Ordered the caps and clips for them. Next week arrival. Hit the starter button today and thought I had a bad starter but I'm thinking the old battery can't cut the mustard. Seems to have the voltage but not the guts to turn the engine. Voltage dipped to 8.6v when I turned on the headlight while it was 12.6v fresh off the Tender. Tried a different starter without success. That's a lot of work to do! Battery hunt time too. Damn all this little picky #$%*!  >:(
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Offline brandEn

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Re: Installing New Style CR Carbs - Couple questions
« Reply #12 on: May 23, 2012, 11:15:53 PM »
The starter jets are completely separate from everything else and I doubt you have a set of spares. They are only used when the start circuit lever is raised during a cold start. You can get by with what you got but after a few cold starts with your fresh rebuild shooting to 8 grand everytime when it fires you might rethink.
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Offline Sam Green Racing

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Re: Installing New Style CR Carbs - Couple questions
« Reply #13 on: May 24, 2012, 04:30:52 AM »
Quote from: MRieck on May 23, 2012, 08:12:36 PM
Quote from: Jerry Rxman Griffin on May 23, 2012, 06:33:34 PM
LMP, thanks for checking in! Michael came through again. That's what I was trying to find out.
I'm going to have drinks with you some day....you know that Jerry.....right? ;D ;D

Jerry, let me give you some sound advise, don't get the old goat drunk. He'll start blathering on about everything and nothing, then He'll want to start kissing and cuddling you cos you're his Bro. ;D ;D ;D ;D ;D

As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Let the party begin Brothers, wish I could be there. ;)

Sam. ;)



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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - Couple questions
« Reply #14 on: May 24, 2012, 10:34:28 AM »
Sam, you CAN be there.  ;D  We just gotta do it  8)

Dammit BrandEn, I'm getting tired of learning all this new stuff  ;D  I just wanna fire it up  >:(  Thanks for the info.
« Last Edit: May 24, 2012, 10:36:06 AM by Jerry Rxman Griffin »
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Offline brandEn

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Re: Installing New Style CR Carbs - Couple questions
« Reply #15 on: May 24, 2012, 11:05:51 AM »
Just passing on all the info I have learned from David and Mike setting up my 29's.
 ;)
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Offline Doctor_D

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Re: Installing New Style CR Carbs - Couple questions
« Reply #16 on: May 25, 2012, 08:52:45 AM »
Quote from: Jerry Rxman Griffin on May 23, 2012, 10:43:13 PM


I have spares - 115 & 125 and 62's (!?!?). Guess I should take a bowl off, huh before installing?! I have Mike's Stage 4 head job with the 34mm intakes to go along with the 900 and Megacycle 125-75. How's that compare to your jetting recommendation?


With K&N's and a 4 into 1, you'll need YY7 needles and somewhere between 128.5 and 132.5 mains.  For better throttle response, use a 2.5 slide cutaway instead of the 3.0 it comes with.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Installing New Style CR Carbs - Back at it - Couple MORE questions
« Reply #17 on: May 28, 2012, 04:17:23 PM »
OK guys, I installed my 1/8" hose connectors into the intakes. Time to install the carbs. From what I've gleaned here it's imperative to install the throttle cables prior to actually installing the carbs. Check. What works easier & best - pull first or push first? Which brings me to my second question - the push has 3 positions it can go into. Which one works best? I have them installed with my push in the top hole but I'm not happy with my return action. The cables are a tight fit, tighter than stock without a doubt, but look like they'll work IF I FIGURE OUT WHAT THE HELL I'M DOING  ;D >:(

Save me from the old install, take off, install, take off, etc vicous carb install cycle!
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Offline JohnN

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Re: Installing New Style CR Carbs - Couple questions
« Reply #18 on: May 28, 2012, 07:41:33 PM »
Jerry:
 I attached stock 750K cables to my CR31's after the carb's were installed without too much trouble. I installed the pull cable first, but had to open the slides all the way to attach the cable end (an extra pair of hands would be helpfull). I used the top hole for the pull cable.

John
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Installing New Style CR Carbs - NEW questions 5/28
« Reply #19 on: May 28, 2012, 09:58:49 PM »
John, thanks for the reply. I'm hooked up but I'm not getting smooth operation or a real return. Aggravating since I'm THAT close.
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