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Switching to Bike Carbs. Heres a write up!

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#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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#2,065 ·
Finally got my carbs on. I am currently running cbr900rr carbs. I put a 42 pilot jet in and a 190 main. The 190 is super rich on wot. But the stock 124 is too lean. I'll try my 180 but will probably end up with a 160 or 170.

I have the tt 254 cams, headers, and 2 1/4 exhaust.

The issue I'm having, is that when i let off the throttle it goes lean. Around 17 or 18:1 afr. If I let it sit and idle for a few minutes it eventually raises back to 14ish:1 afr. My mixture screws are set 5 turns out at this point.

As soon as I give it any throttle itll richen up and be fine, but clutch in and off throttle drops again.

Any ideas? I've also cleaned them already, and synced them.


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#2,066 ·
As soon as I give it any throttle itll richen up and be fine, but clutch in and off throttle drops again.
You may want to try using 50 pilot jets. 42 is a bit small, it may be why you're leaning out off throttle. Off throttle and idle is primarily what the pilot jets handle.

190 may be a tad much for the mains as well, I'd grab some 180's while you're on the hunt. Rule of thumb for bike carbs, if you're more than 2.5 turns out, you need to rejet.

Report back and let me know if it helped!
 
#2,067 ·
So I put 160s in for mains. I'm around 13.5 under wot which I'm happy with. Plus I have jets all the way to 190 so I've got options. I also drilled out my pilots to .4mm. Stocks were .3mm. Idle is still a little lean but not horrible around 16 to 17:1. But cruising is around 12-13afr. Which is a bit rich for cruising imo. I'd like to be closer to 14-15.
However, if I go smaller on the pilots my idle still wont be rich enough.
I'm at a weird kind of stand still.

I've also noticed that after driving my car for a bit, the idle will raise about 200rpms at idle. And it rev hangs quite bad too which makes me think it's just dumping fuel. Or maybe my fuel pressure is too high. Although it reads at 1psi.

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#2,069 ·
Weird. The only thing I can think is the fuel isnt getting mixed well enough with the air because it's not sucking in as much as the bike would at idle. Or maybe it is the fuel psi. I've been messing around. And I'll keep doing so because I love these carbs haha.

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#2,070 ·
What are you doing for ignition timing, do you have vacuum advance? If-so, where (and how) are you pulling vacuum from? If pulling from a single runner that may not be enough.

This just covers the basics, but it's a good start: https://www.classiccarrestorationclub.com/article/carburetor-tuning-ignition-first/#

And this one (read down a bit) gets into things a bit more: http://www.superchevy.com/how-to/additional-tech/1601-everything-you-wanted-to-know-about-vacuum-advance-and-ignition-timing
 
#2,072 ·
Got a wiring question about the ICM. Not running a knock box, using a full msd setup. All the wiring diagrams I’ve found show 4 wires but my plug has 6 wires in the 7 pin connector and three of those have been spliced into the distributor plug.

Anyone have the wiring for the 6 wire plug? I’ve looked in the Bentley and don’t see any wiring diagram that has 6 wires for the ICM.




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#2,076 · (Edited)
Hi there guys,

Just swapped my 79 Rocco with a 16v 9A bloc, ABF cams and R1 Carbs. Standard electronic ignition that i had already in the car, with a vacuum distributor.
Jets are 180mm Main, 50 Idle.

The car started right up, no problems there. But it is really smoking black. Not even exagerating, you can't stay behind the car without suffocating. And when in a Red Light, well..... a nightmare for those how are behind me :facepalm:

The head was done with new seals and valves, the bottom end is stock, nothing done to it, it has 180k kms (112k miles)


Since the carbs are putting more gas in, do i need to go with another oil than the one stock for this engine?
Now i'm running with the 10W40. Searched all of this topic for oil posts, but found nothing clear and precise, to what people have been running with a similar set up.

Should i try another oil? Do the 16v engines accept 20w50 oil?
Or i have no choice and do the bottom end, piston rings, etc?
 
#2,078 ·
Hi there guys,

Just swapped my 79 Rocco with a 16v 9A bloc, ABF cams and R1 Carbs. Standard electronic ignition that i had already in the car, with a vacuum distributor.
Jets are 180mm Main, 50 Idle.

The car started right up, no problems there. But it is really smoking black. Not even exagerating, you can't stay behind the car without suffocating. And when in a Red Light, well..... a nightmare for those how are behind me :facepalm:

The head was done with new seals and valves, the bottom end is stock, nothing done to it, it has 180k kms (112k miles)


Since the carbs are putting more gas in, do i need to go with another oil than the one stock for this engine?
Now i'm running with the 10W40. Searched all of this topic for oil posts, but found nothing clear and precise, to what people have been running with a similar set up.

Should i try another oil? Do the 16v engines accept 20w50 oil?
Or i have no choice and do the bottom end, piston rings, etc?


pic of the beast ;)

Black smoke is fuel, not oil. Oil smoke is blue. What is your fuel pressure? If you pull the dipstick does the oil smell like fuel? Float level ob the carbs? Idle bleed screw adjustment?

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#2,079 · (Edited)
First thing I think of with black smoke is that you're running really rich. The way you describe it makes it almost sound impossibly rich (like it wouldn't even run well) but still...

Do you have a wideband O2 gauge?

And do you have a pressure gauge on the fuel feed line to the carbs?

Do you have your choke hooked up? Perhaps it's on choke and you don't realize it?

Very nice setup by the way, that looks great. :thumbup: :thumbup:
 
#2,081 ·
So car runs pretty damn good, but according to my afr gauge its rich io top. Close to 11 still. I've got slightly larger mains, I think 150s iirc. The pilots were changed out for two sizes larger so that itd idle and decel properly. Do i need smaller mains?? I'm really close to swapping a 1.8t in lol.

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#2,084 ·
I need some education...

I bought the car with a 2.0l 16v with R1 carbs. Having some running rich issues after messing with things. I recently replace the jets and almost ready to put the carbs back on the car however the carbs had the throttle switches from the regular throttle body connected to the carbs. One of the wires has came loose from the idle throttle sensor so I was looking to replace with another set of throttle switches I had in the parts bin. I cannot get the switches to line up so the idle switch is pressed in at idle and the WOT switch press when wide open.

I don't really understand what this system does. Can anyone explain? Also is there a different/better way to do this. Ive included some photo which hopefully show my setup.

Also, I have seen reference to Air/Fuel gauges. My car does not have one installed. What would be recommended as a setup for this?

Thanks

[/url]IMG_2122-1 by Photography Dish, on Flickr[/IMG]

[/url]119480165_10158488053747209_3169879408630457300_o by Photography Dish, on Flickr[/IMG]

[/url]119330607_10158488052657209_6203220284465186965_o by Photography Dish, on Flickr[/IMG]
 
#2,086 ·
i need some education...

I bought the car with a 2.0l 16v with r1 carbs. Having some running rich issues after messing with things. I recently replace the jets and almost ready to put the carbs back on the car however the carbs had the throttle switches from the regular throttle body connected to the carbs. One of the wires has came loose from the idle throttle sensor so i was looking to replace with another set of throttle switches i had in the parts bin. I cannot get the switches to line up so the idle switch is pressed in at idle and the wot switch press when wide open.

Simply repair the wire in the switch, you cant line up the switches because they are different ones.

I don't really understand what this system does. Can anyone explain? Also is there a different/better way to do this. Ive included some photo which hopefully show my setup.

The wot switch plays a role in the ignition timing, but only when you´re using the ignition control module from the r1, i think you´re not, so this is irrelevant.

What was the switch connected to?

Also, i have seen reference to air/fuel gauges. My car does not have one installed. What would be recommended as a setup for this?

Thanks

[/url]img_2122-1 by photography dish, on flickr[/img]

[/url]119480165_10158488053747209_3169879408630457300_o by photography dish, on flickr[/img]

[/url]119330607_10158488052657209_6203220284465186965_o by photography dish, on flickr[/img]


simply repair the wire in the switch, you cant line up the switches because they are different ones

the wot switch plays a role in the ignition timing, but only when you´re using the ignition control module from the r1, i think you´re not, so this is irrelevant.

What was the switch connected to?
 
#2,091 ·
More great info in here, thanks guys!

Today I dug my project out from under the piles of crap it has accumulated over the years. Really just to be able to move it out of the garage to work on other projects in the space. I did get to open the hood and gaze upon it for a bit, though!

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#2,092 ·
Hi all, here is what i did, hope it will be useful

Engine 1.8 8V, CBR 900RR carbs, stock ignition, centrifugal dizzy with vacuum advance unpluged, mechanical fuel pump with fuel restrictor to carbs.
Number of testslow jet sizeidle screws turns outmain jet sizeNeedle jet heightResults
1403155standardGood idle, no throttle response and low power with bad revving, running hot and too lean
2403165standardGood idle, no throttle response and low power with bad revving, running hot and too lean
3403180standardGood idle, no throttle response and super bad revving and no power at all, really bad MPG, super black spark plugs with carbon fouling, running super rich
4501.5165standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
5501.5155standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
6501155standardBetter idle, better throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich
7503/4150standardgood idle, good throttle response and revving, feels more power, better MPG, spark plugs very with light carbon build up, running rich yet
8501/2150standardgood idle, good throttle response and reving, can feel the power, nice MPG, spark plugs with very light carbon build up almost unperceptible, running almost normal
At this point i get an AFR narrow band gauge, the numbers at idle was oscilating between 14.3-14.6, at WOT oscilating between 12.3-13, maybe use a 140 mains, play with needle heights and see what happens
 
#2,093 ·
New update:

Engine 1.8 8V, CBR 900RR carbs, stock ignition, centrifugal dizzy with vacuum advance unpluged, mechanical fuel pump with fuel restrictor to carbs.
Number of testslow jet sizeidle screws turns outmain jet sizeNeedle jet heightResults
1403155standardGood idle, no throttle response and low power with bad revving, running hot and too lean
2403165standardGood idle, no throttle response and low power with bad revving, running hot and too lean
3403180standardGood idle, no throttle response and super bad revving and no power at all, really bad MPG, super black spark plugs with carbon fouling, running super rich
4501.5165standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
5501.5155standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
6501155standardBetter idle, better throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich
750 3/4150standardgood idle, good throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich yet
850 1/2150standardgood idle, good throttle response and revving, can feel the power, nice MPG, spark plugs with very light carbon build up almost unperceptible, running almost normal
At this point i get an AFR narrow band gauge, the numbers at idle was oscilating between 14.3-14.6, at WOT oscilating between 12.3-13, maybe use a 140 mains play with needle heights and see what happens
950 1/2140standardgood idle, good throttle response and revving, +-25 MPG, spark plugs with no carbon build up, running normal, 14.3~14.6 at idle, 13~14 at WOT
 
#2,094 ·
New update:

Engine 1.8 8V, CBR 900RR carbs, stock ignition, centrifugal dizzy with vacuum advance unpluged, mechanical fuel pump with fuel restrictor to carbs.
Number of testslow jet sizeidle screws turns outmain jet sizeNeedle jet heightResults
1403155standardGood idle, no throttle response and low power with bad revving, running hot and too lean
2403165standardGood idle, no throttle response and low power with bad revving, running hot and too lean
3403180standardGood idle, no throttle response and super bad revving and no power at all, really bad MPG, super black spark plugs with carbon fouling, running super rich
4501.5165standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
5501.5155standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
6501155standardBetter idle, better throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich
7503/4150standardgood idle, good throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich yet
8501/2150standardgood idle, good throttle response and revving, can feel the power, nice MPG, spark plugs with very light carbon build up almost unperceptible, running almost normal
At this point i get an AFR narrow band gauge, the numbers at idle was oscilating between 14.3-14.6, at WOT oscilating between 12.3-13, maybe use a 140 mains play with needle heights and see what happens
9501/2140standardgood idle, good throttle response and revving, +-25 MPG, spark plugs with no carbon build up, running normal, 14.3~14.6 at idle, 13~14 at WOT
Some pics:
62265
62267
62268
62269
62270
 
#2,098 ·
Quick question in regards to msd wiring. According to the msd only thing going to the coil should be the two msd wires.

Mk1 wiring had a neg wire for the starter and I believe the other went to the fuel pump relay.

How did y’all rewire your setup.


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#2,100 ·
Man, that's a really nice quality job on the intake manifold! I like how you used the motorcycle couplers on a mounting flange. I had considered that for my old setup but went the easier route of fuel hose couplers. I'm surprised you didn't take advantage of those four small vacuum nipples. Are you drawing vacuum from somewhere else?
 
#2,102 ·
The last adjustments and definitive setup:


Engine 1.8 8V, CBR 900RR carbs, stock ignition, centrifugal dizzy with vacuum advance unpluged, mechanical fuel pump with fuel restrictor to carbs.​
Number of testslow jet sizeidle screws turns outmain jet sizeNeedle jet heightResults
1403155standardGood idle, no throttle response and low power with bad revving, running hot and too lean
2403165standardGood idle, no throttle response and low power with bad revving, running hot and too lean
3403180standardGood idle, no throttle response and super bad revving and no power at all, really bad MPG, super black spark plugs with carbon fouling, running super rich
4501.5165standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
5501.5155standardBad idle, better throttle response and better revving, feels a bit of power, bad MPG, black spark plugs with carbon fouling, running rich
6501155standardBetter idle, better throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich
750 3/4150standardgood idle, good throttle response and revving, feels more power, better MPG, spark plugs with light carbon build up, running rich yet
850 1/2150standardgood idle, good throttle response and revving, can feel the power, nice MPG, spark plugs with very light carbon build up almost unperceptible, running almost normal
At this point i get an AFR narrow band gauge, the numbers at idle was oscilating between 14.3-14.6, at WOT oscilating between 12.3-13, maybe use a 140 mains play with needle heights and see what happens
950 1/2140standardgood idle, good throttle response and revving, ~25 MPG, spark plugs with no carbon build up, running normal, 14.3-14.6 at idle, 13-14 at WOT
After around 200 miles of driving the spark plugs shows very little carbon build up may be caused by the combination of slow and main jets at middle range throttle so the slow jet was replaced with a 45 size
10452 1/2140standardNot yet, check pending
After driving around 100 miles take out the plugs and it seems OK no carbon build up at all, wet or oil. I think i get the correct AFR mixture, got a decent MPG (~4.5 gal in 100 miles) so i decide use this setup permanently.​
11453 1/8140standardChange the mixture in the idle jet by using the idle screw (3 1/8 turns out) after experimented little power at low RPM, issue was corrected
 
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