16v on bike carbs, they're on at last... P5

Turns out the fpr could not go low enought so i fitted the original R1 pump and its fine. The only problem i have is that there is fuel comming from around the needle at idle, and while the idle mix is good ( i checked with a colour tune) there is less coming from the idle jet. As far as i know there should only be fuel from the needle at more than 1/4 trottle , up to this point its all from the idle jet. I have raised the circlip on the top of the needle , it has helped but its still leaking fuel. I drilled the main jet to 1.8mm which is about right for a 2 liter but maybe its too big??

 

what pressure have you got though? they are notoriously sensitive to a couple of psi too much or too little , you'll have to check it to be sure .

 

I don't know what pressure but it is the original pump so the pressure should be fine.

 

any ideas where to get the hose to join carbs to manifold as i'm being told quite often that normal hose will rot with the petrol going thru it?! cheers!

 

yes, normal hose will rot but this hose is fuel resistant and i have no idea what its from but it has a wall thickness of about 5mm, but its not a perment fix, i'l have to make one from steel or alu. but i'll see how long this lasts.

 

Hurrah!

Brilliant post dudes- im gonna join in this one as ive slowly been collecting:

1 x VW Golf Mk1 in sexy silverpurple chav-flip (ah well cant all be good..)
1 x Cable change box (i will be doing 70miles a day commute...)
1 x Cable change selector (as above)
4 x Mikuni R1 carbs (need a bogg bros rejet- im not comfortable with jet drills yet..)
1 x 2.0 16v 9a with a lightened Mk3 flywheel/clutch
1 x KR head
1 x KR manifold (to do exactly as Jamez did- great idea!)
1 x welder (to make the gearbox mounts/exhaust manifold

i still need to pick up a red top pump and a filter king (ive heard about the pressure issue so im getting the one with the gauge on it for precise adjustment)

I will be taking plenty of pics, i will post and drawings of the gearbox mounts/manifold etc as i go- i love welding Also a full small-diameter multi-piece rollcage for safety when ragging it up the A34 playing lorrytag and to pacify my nervous girlfriend....

It will all kick off this weekend cant wait!!

That 'Rado is all the inspiration i need right now- top marks

 

make sure you guys use vacuum specific hose, or it'll get sucked flat on a closed throttle

 

Is what i had to do was fit some thin walled steel pipe inside the tubing as the vacume would certainly crush the tubing alone, it now runs well but i have to sort the problem with the fuel flow from the needle at idle.The needle looks very narrow, i'll fit a standard needle, should sort the problem. I'll try get a vid at weekend.

 

Hey Redlexus can we pick your brains if you have done the conversion?

I was wondering if you could explain the carb setup in a bit more detail- ive got a 2.0 VW lump so im guessing the airflow and fuel requirments are similar to the 2L Zetec and so do you reckon your choice of Weber idle and main jet needles will work fine?

I have been looking at the Weber parts lists on www.fastroadcars.co.uk, the main jet numbers you mention make sense (for DCOE/IDF & IDA carbs, sizes 100-230) but can you tell me which idle jets you've used?

Im presuming the Keihin CBR900 carbs use the same jet design as the Mikuni R1 carbs as they are both the CV type and so the needles you chose will at the very least get my engine running so i can get it to a rolling road for fettling?

Also Ive been looking at the Facet/FilterKing fuelling route but do you know if the original bike pump will work, sounds useful if it has a pressure cut-out but can it constantly supply the higher volume of fuel to run a 2L engine?

Thanks so much for your help- im trying to keep the project cost down and as my carbs are in perfect condition im damned if im gonna pay Boggbros (or similar) to rebuild/rejet the carbs when i can just buy and fit/refit the jets myself!

Ta for now

 

As it turns out the manifold i made from the flex pipe was , as expected not good, so i made an attempt at another this time with steel pipe but as the plate is aluminium i can't weld it, so i mitered the ends of the pipe and slightly flattened one end to match the inlet shape and connected with the hose and clamps. This works much better, but the idle is a bit lumpy from the 278 cams, may go a bit less.Also made and fitted a spacer for the exhaust manifold as the lower part was fouling the inner c.v. boot and melted a bit in traffic.

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iv got a 1.9 16v on gsxr bike carbs on a home made manifold..had it set up a couple of weeks back and made 190hp on a otherwise standard engine..im using a H+H ignition system but havnt fitted it yet.

 

Thanks god for that.. Looks exactly like mine will once its finished.. Was starting to think it wouldn't work lol

Seems a lot of people are doing this now so there should be some good DO's and DONT's that come out of it.

Ive priced up the manifold and to be honest its far far cheaper to make my own. I managed to pick up a flat bar of steel for around 3, and for the sake of a couple of hours welding im saving a hell of a lot of money.


My current costs are

Mk2 and Engine ( ABF+ Box etc 82k miles) 400
Both in very very good condition ( only need to weld rear arches, but decided to strip and redo the whole car) plus nearly new stainless exhaust and other bits

GSXR 1100 MIKUNI's ( 40mm) 70 -

Flat bar of steel and gasket to make Inlet manifold 3

Dizzy and coil to run spark 10 ( NOT vw sorry )

Currently trying to figure out a way of getting around using an after market FPR to keep costs down ( also trying to keep engine bay as clean as poss)

Currently collecting bits,will get some pics when i have got everything together and start working on the shell.

The car will be a weekend/summer toy and track day play thing so thankfully ive got quite a bit of time to get it sorted.

 

Hi. new to this forum. there seems to be more threads on bike carb conversions than any where else. I'm in the final stages of fitting a KR16v into a Mk1 caddy and need to know what you guys are using for choke cable and throttle cables. My Caddy is LHD so I have got problems finding a long choke cable with the barrel type nipple on the end.
I've posted pictures in the members motors section if you want to see the set up. Also be interested to know what size is recommended to drill the jets out to? or I'm I better off buying weber jets

Pictures
http://www.clubgti.com/forum/showthread.php?t=158924

You can also see the whole process on the Caddy forum at
http://www.vwcaddy.com/showthread.php?t=18198

Thanks

Steve

 

I've been studying intake systems for a while now , and it seems that the best length for one is between 300 and 350 mm from the inlet valve face to the outside of the carb trumpet . Longer for torque low down , shorter for hi-rpm power . So our Ford manifold above is a fair bit too long .

 

Also I wouldn't panic too much about having the fuel bowls perfectly level , like we did,,, think about the way the biker nutters go down long straights doing wheelies , and they never seem to splutter!

 

Hi guys. In the final stages of fitting a KR1800 16v into a MK1 Caddy..... On R1 carbs. There seems to be a good depth of knowledge on this subject on here so stand-by for a few questions.... If posted a few pic's in the Members motors section but here's where I'm at at the mo



As you can see the carbs are not properly fitted yet as I'm working on a solution for the top water hose. Made up the manifold myself out of steel... have made a template so if all goes well I'll get a stainless one knocked up. Exhaust is an Ashley.

Ok questions. What are people using for throttle cables.... the original VW one has the wrong fitting at the carb end.

Main jets. Whats recommended... ? Is it best to drill or is it best to buy Weber jets

Hope to be finished with this for Easter so need to get my finger out really.

Any input would be great.

S

 

This might be me just being rely dim but why couldn't you just substitute your high preassure injection pump for a low preassure carb one? then cap off the return feed and add a swirl pot to keep the fuel constant? all stuff from the scrappy for peanuts... and you could sell your old pump on ebay to recoup your outlay...

 

I have replaced the original fuel pump with the original from the R1 which i got for 35 euro, so no other work required except a filter. As for the cabels i used a brake cabel from a bicycle with an adjustable, fixed with a screw, type barrel for the trottle cabel as it has the nipple on one end for the carb side. The only problem i have is that if i fix the cabel to the original position on the accelerator pedal, there is very little travel in the pedal, so i'll try to move the cabel down lower in the bulkhead to get full travel in the pedal.

As for the choke , the original cabel was used but the cabel i attached in reverse. The nipple is attached the the end but when the choke is used its he sleeve that moves and not the internal wire, but mine is lhd so the cabels come from the other side.

Also on advice i have purchased megajolt for the ignition from the usa to get the best from the carbs.

 

hi after reading this thread i decided to do this with my mk2 2.0 16v. im using keihin cdk 40 carbs and a r1 fuel pump. plumbed it all in and is running nice, only problem ive got is that when you press the accelerator thers only about 2 inch of travel between idol an full throttle! is there any way of adjusting it? its hard to drive with my big feet!

 

just thought id post pictures of my conversion and a ruff costing so far. car is running but needs a longer choke cable and rolling road tuning. its all based on a 9a 2.0 16v with kr head and cams. was last setup on k-jet and made 170 bhp so will be interesting to see what happens this time. sound is amazing!!

40mm keihin carbs (kwak ninja 900) 50 ebay
inlet manifold (16v cut down and rewelded) 65 local ali fabricators
yamaha R1 fuel pump (has built in fpr) 35 ebay (remove existing pump and put r1 in its place. blank off the return pipe-not needed)
inline glass fuel filter 8
one 12inch lenght of 50mm silicone hose to connect carbs to manifold 10
various lenths of fuel hose and vacuum hose clips etc 20

total of 188. bargain!