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Switching to Bike Carbs. Heres a write up!

876K views 2K replies 169 participants last post by  Saves 
#1 ·
Switching to Bike Carbs. Heres a write up!... IT IS COMPLETE!

Hello everyone!
This is going to be my first write up. Please feel free to ask questions and make suggestions! http://****************.com/smile/emthup.gif By the end of this build i hope to have step by step instructions so that all you good folks out there can set up some bike carbs too!

I recently traded my 77 rabbit for an 82 Caddy with a 2.0 swap. The CIS fuel system was never fully installed, and is currenty hooked up just so that it gets me from A to B. I have been researching on what route i want to go with the fuel system and have decided to go with some bike carbs! My reason for this choice is my extreamly limited budget (Currently going to tech school, typical poor student
), the ease of the install, and the effeciancy of bike carbs over Weber carbs.
My plan is to gather and fabricate all of the needed parts and then spend my Winter break installing and tuning the carbs. I will be trying to contact "Bogg Brothers" to figure out what jet sizes i need and order a few smalll parts.
Parts List Needed (please contribute if im missing parts):
Bike Carbs
Correct Jets
Fuel Pressure Regulator
Manifold
Fuel Hose
Tonight is day one of my gathering. I purchased a set of Yamaha YZFR1 Carbs off ebay. I cant wait for them to arrive so i can get them all cleaned up! Ill begin posting pics ASAP.
Here is an artical and a couple vids to get you PUMPED!
http://www.totalvauxhall.co.uk...7.pdf
http://www.youtube.com/watch?v=Tb7ILh6ZxxA
http://www.youtube.com/watch?v...lated


Modified by Miami Blue at 10:35 PM 1-3-2010
 
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#19 ·
Re: (Flyingsheep)

On my engine i will have to move the alternator down to where the AC comperssor is located. Which means no more AC for me http://****************.com/smile/emthdown.gif. Im just using the existing bracket, not a serpentine set up.
Today I picked up one of those cheap FRAM filters FROZEN was talking about
. Ill eventually get a better one.


Modified by Miami Blue at 4:43 PM 11-15-2009
 
#22 ·
Re: (B4S)

Quote, originally posted by B4S »

Absolute myth. If you look up the specs of the carter, it's WAY more than most sidedraft style carbs need. If it's running without an FPR, then there is also something wrong with the setup that is limiting the fueling, like too-small needle valves, or restrictions in the lines.

Quotes from Summit regarding the Carter 4070 Pump:
"They also have an internal pressure-regulating valve" and "A regulator is not required."
The pump DOES have a regulator, but it says nothing about being adjustable.... A little bit of a misleading product description
...


Modified by Miami Blue at 10:00 PM 11-15-2009
 
#24 ·
Re: (Miami Blue)

Quote, originally posted by Miami Blue »
Before i go and build my manifold... Does anybody know about powerband tuning using the length of the runners?

I built mine to fit in the bay!
 
#25 ·
Re: (FROZEN337)

Quote, originally posted by FROZEN337 »

I built mine to fit in the bay!


Im talking about using the length of the runners to determine at what RPM's the engine makes more power.
Ill just make up a few sets of velocity stacks later on and see which ones work the best.


Modified by Miami Blue at 4:12 PM 11-16-2009
 
#26 ·
Re: (Miami Blue)

When I built my mani, I made it short enough to mount the carbs and filters, it is tight in there, I just wanted them to fit. If I ever go to a smaller rad, I will play with another mani and stacks.
 
#28 ·
Re: (Miami Blue)

I'd like to see some hard data on the use of velocity stacks to tune the runner length. My understanding on runner length is back of the throttle plate to the back of the intake valve, as its timing the pulses between the closed valve and the throttle plate that "tunes" it to a certain rpm range. Longer runner length tunes it to lower rpm as there's more time between valve openings. Short runners, higher rpm, less time. That's the basics of it. You need a lot of VE info to really calculate out runner length to tune it properly, though. I'm not saying you can't tune it with velocity stacks, I've just not seen it and it goes against what I was taught. Not saying this makes me an expert, by any means, but just to quantify a bit, I do hold an Associates Degree in Motorsports Technology.
 
#29 ·
Re: (YJSAABMAN)

All input is welcome man! If i could find a dyno to use id experiment with the velocity stacks. Like i said... maybe in the future. Where did you go to school to get your degree?
As far as updates on my little project here go... I picked up flange materials today and used a gasket to draw up what i want the flange to look like. Now i need to find someone to cut it, nothing i have can handle 1/2 inch.
Tonight im gonna order some goodies from Summit... Yippee!
Flange stuff:
 
#30 ·
Re: (YJSAABMAN)

Quote, originally posted by YJSAABMAN »
Not saying this makes me an expert, by any means, but just to quantify a bit, I do hold an Associates Degree in Motorsports Technology.

Im a truck driver in the Army, you got me beat!
If you can find someone with a plasma cutter, it will be easy and clean.
 
#31 ·
Re: (FROZEN337)

I asked the metal shop if they could plasma cut it but they said it was too thick. Im going to go back tomorrow and see if they can use the shear cutter and get the straight lines pretty close. I dont mind doing some grinding and drilling for the rest of it, we got the right tools for that at the race car shop http://****************.com/smile/emthup.gif
 
#33 ·
Re: (Flyingsheep)

Went to (believe it or not) a little community college in NEPA. Had a full automotive machine shop, flowbench, fab shop, etc. And the instructors all worke din the industry building engines or doing chassis fab/custom machine work. Awesome program!
Agreed on the material, 3/8" should'v ebeen plenty. I don't think you're going to find a shear that can handle 1/2". I have to admit, I'm not as big a fan of plasma as waterjet, if I had the choice. Plasma still leaves a pretty rough edge, especially on the thick stuff, and you really need to have a steady hand. Lots of grind time after plasma. If you can get access to an upright band saw you should be able to rough it in very close and then spend a little cleanup time on a grinder.
 
#34 ·
Re: (YJSAABMAN)

I had to use a bandsaw to clean my flange up, or I would not have been able to get my spark plugs in! I say plasma only because you should be able to find one you can use before you find you find a water jet.
Almost anyone can use a plasma cutter, ALMOST!
 
#35 ·
Re: (Flyingsheep)

Quote, originally posted by Flyingsheep »
Where do you get the flange material? Couldn't get anything thinner?

Any metal supplier has the material. I could have went with thinner steel yes, i chose to go with 1/2 inch because thats about what the stock flange is. Also after the runners are welded on im going to have a machine shop mill down the back side so that its perfectly flat, so it will be a little thinner.
Took the plate i bought yesterday back to the shop and they were happy to make the cuts for me. They used a large band saw for the longer cuts and the shear for the rest. The amount of force that that machine has is amazing! Thats hydraulics for ya!
Im going to UTI right now, i wish it had some fab classes in the program. After i graduate i plan on going to community college and taking some engineering and fabrication classes, im more interested in that stuff.
Gonna grind down the outside edges tonight and clean them up. Hopefully ill have it finished this weekend.
 
#40 ·
Re: (Miami Blue)

Sent a couple messages out on youtube to guys who had posted their R1 swaps last night. I asked them about what jet sizes they ended up going with, i must say, im very pleased! Both of the guys used pretty much the same size jets on their 16v 2.0 engines!
Messages:
"my carbs are on a 1.8 as a start ive used 1.6 but told by the engine tuner i could easily go to 1.65 , my mate who,s got a 2.0 but has a few more mods and mega jolt ingnition is on 1.83 i think"
"hi they drilled them to 1.8 mm , but it was under fueling at high revs , i drilled them out to 2mm and the carbs fuel well up to 7,500 rpm. if you need any other info just contact me , regards jayson"
So it looks like 1.8mm will be the jet to start with!
Im thinking of putting a Saab 900 non turbo dizzy on that has vacuum advance. Does anyone have any info on how well these work on a 9a engine? Im sure ii works way better than my CIS-Motronic dizzy that isnt plugged in to anything...


Modified by Miami Blue at 9:29 PM 11-20-2009


Modified by Miami Blue at 11:11 PM 11-21-2009
 
#41 ·
Re: (Miami Blue)

My carbs FINALLY came in today!! Yeeeha! I cleaned the outside up real good first thing, there was some grime on em. Tonight ill open them up and clean them some more. I need to find a manual on these things so i can figure out where all the fittings go. Does anyone knoe offhand what goes where?




And my parts that i have gathered so far: My finished flange, choke cable, fuel filter, pressure gauge, and fpr. All i should need now is fuel hose, runners, and silicone hose for attaching carbs to manifold.

For some reasson my camera likes to switch between black and white, and color
.... Oh well!


Modified by Miami Blue at 6:17 PM 11-27-2009
 
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