Switching to Bike Carbs. Heres a write up!

[rysskii3]

Yes, I had to force fuel through them a few times, now it starts with just a key turn.

Sweet

[oldschool eighty8]

crappy point and shoot video.
fans arent working properly so I haven't really tuned it yet

[pnavarro]

Niiiice!

[rysskii3]

crappy point and shoot video.
fans arent working properly so I haven't really tuned it yet

[rysskii3]

[oldschool eighty8]

good choice! I have the same one

[rysskii3]

good choice! I have the same one

no idea how it works, but it does look good while the car is in the garage.

[oldschool eighty8]

Still having troubles with cold starts, doesn't seem to want to pull fuel in, I've swapped out the starter for a high tourqe one so its cranking at a good rpm. Any ideas? If I blow into the two plastic vents on top of the carbs it starts right up, and once it's built up some heat it will start on it's own.

[rysskii3]

Still having troubles with cold starts, doesn't seem to want to pull fuel in, I've swapped out the starter for a high tourqe one so its cranking at a good rpm. Any ideas? If I blow into the two plastic vents on top of the carbs it starts right up, and once it's built up some heat it will start on it's own.

its pretty normal for carbs to have a hard time starting up when its cold. what oil are you using?

[oldschool eighty8]

Right now I just have some castrol 10-30 in it that I had sitting in the garage I plan on switching to something else once it's broken in. If I don't blown into those two vents it won't even stutter like it's trying to start it just cranks.

[junn1227]

I own a 1979 MK1 Rabbit and recently got the 16v bike carb (R1) set up running. I'm experiencing issues with motor vibration and fuel pressure. The rough fuel pressure may be contributing to the vibration of the motor but it is quite insane. The motor vibrates likes its on a shaker table and it's annoying the heck out of me. Cold starts especially and gets a little better after the engine warms up, but still noticeable. What could be the culprit? The engine mounts will soon need to be replaced but I feel like it's much more than that.

The fuel pressure is inconsistent. I sometimes get 2.5 - 3 psi but today seeing only 1 psi. I'm running a Carter fuel pump and Holley FPR with 1.75 main jets. Should I go up to 2mm jets? I did notice fuel seeping out of the carbs, could that be contributing to the loss in fuel pressure?

Any input is much appreciated.

[rysskii3]

Right now I just have some castrol 10-30 in it that I had sitting in the garage I plan on switching to something else once it's broken in. If I don't blown into those two vents it won't even stutter like it's trying to start it just cranks.

I haven't any problems starting on 10w30, but when i changed it to 50 weight full racing oil, I did notice that cold starts are taking a long time. I have to prime the carbs for a little and then play with the throttle to get it started. Once the car is warm, no problems.

I own a 1979 MK1 Rabbit and recently got the 16v bike carb (R1) set up running. I'm experiencing issues with motor vibration and fuel pressure. The rough fuel pressure may be contributing to the vibration of the motor but it is quite insane. The motor vibrates likes its on a shaker table and it's annoying the heck out of me. Cold starts especially and gets a little better after the engine warms up, but still noticeable. What could be the culprit? The engine mounts will soon need to be replaced but I feel like it's much more than that.

The fuel pressure is inconsistent. I sometimes get 2.5 - 3 psi but today seeing only 1 psi. I'm running a Carter fuel pump and Holley FPR with 1.75 main jets. Should I go up to 2mm jets? I did notice fuel seeping out of the carbs, could that be contributing to the loss in fuel pressure?

Any input is much appreciated.

Is the fuel leaking from the fuel bowl? If so, replace the gaskets. Changing fuel jets can cause more problems unless you run a wideband and know what your AFR is.

[junn1227]

Is the fuel leaking from the fuel bowl? If so, replace the gaskets. Changing fuel jets can cause more problems unless you run a wideband and know what your AFR is.

Yup, fuel is leaking from the fuel bowl. I'm ordering the gaskets from a nearby Yamaha dealer tomorrow. I'll try to work with the fuel jets I have now but a wideband is something I'm considering in the near future. Can't wait for this baby to be my dd

[oldschool eighty8]

I haven't any problems starting on 10w30, but when i changed it to 50 weight full racing oil, I did notice that cold starts are taking a long time. I have to prime the carbs for a little and then play with the throttle to get it started. Once the car is warm, no problems.

I've tried letting it prime for a bit and playing with the throttle, no deal. It will crank till the battery dies before it will start if I dont manually force fuel in.

[rysskii3]

I've tried letting it prime for a bit and playing with the throttle, no deal. It will crank till the battery dies before it will start if I dont manually force fuel in.

i dont know what to tell you there

[oldschool eighty8]

i dont know what to tell you there

Yeah, I don't get it either. It's a simple set up. I'm going to pull them apart and clean them really good, if that doesn't work then I'm ditching them for somehing else.

[rysskii3]

Yeah, I don't get it either. It's a simple set up. I'm going to pull them apart and clean them really good, if that doesn't work then I'm ditching them for somehing else.

I'm afraid to pull mine apart. But i am taking the car very soon to get dyno tuned.

[ncbrock]

I'm afraid to pull mine apart. But i am taking the car very soon to get dyno tuned.

Bike carbs are stupid simple to take apart.

[rysskii3]

going back to filter conversation from a while back. i decided to get k&n universal cone filters RU-2320 or RU-2930.
the 2320 is slightly (0.8cm) longer than 2930, but other than that they are both identical. does it matter which one i pick in terms of performance?

2320


2930

[yeayeayea]

I would get the bigger filters if you can fit them. which likely wont be the case unfortunately

[rysskii3]

I would get the bigger filters if you can fit them. which likely wont be the case unfortunately

The bigger filters would fit fine, the set I have now is actually 3-5mm longer.
I called the dyno shop that will be doing the tuning also recommend the larger filters. Funny thing is that larger filters are cheaper.

[funpig]

With the difficult startups you guys were talking about earlier..... do you have a choke cable setup? I had problems initially but once I hooked up the choke I can start my little pig anytime regardless of the weight of the oil.

On another note.... any of you guys having problems with oil pressure blowing out your seals? I have changed both my front and rear mains twice now and that works fine for a short time but I start leaking oil like a little bish. Its getting terribly frustrating. I installed a catch can which I thought would help but I am still leaking and also noticed oil coming up around the bushing around the distributor even though I have changed those O-rings twice as well.
THoughts???

[rysskii3]

With the difficult startups you guys were talking about earlier..... do you have a choke cable setup? I had problems initially but once I hooked up the choke I can start my little pig anytime regardless of the weight of the oil.

On another note.... any of you guys having problems with oil pressure blowing out your seals? I have changed both my front and rear mains twice now and that works fine for a short time but I start leaking oil like a little bish. Its getting terribly frustrating. I installed a catch can which I thought would help but I am still leaking and also noticed oil coming up around the bushing around the distributor even though I have changed those O-rings twice as well.
THoughts???

i cant even start with choke on. i havent had any seals pop but i do have a valve cover connected to a catch can.

[oldschool eighty8]

I don't have a choke either, but I've figured out the issue.. Combination of the carbs not staying primed and my mega squirt warmup settings being way off.

[rysskii3]

I don't have a choke either, but I've figured out the issue.. Combination of the carbs not staying primed and my mega squirt warmup settings being way off.

No, I have the choke cable. The car just doesn't like starting on it.

[rysskii3]

No, I have the choke cable. The car just doesn't like starting on it.

i think im going to switch from valvoline vr1 sae 50 to vr1 20w-50. maybe that will help with easier start ups.

[oldschool eighty8]

i think im going to switch from valvoline vr1 sae 50 to vr1 20w-50. maybe that will help with easier start ups.

Yeah that stuff is super thick!

[YJSAABMAN]

@ rysskii3: Just run a piece of vacuum tubing into the cabin so you can blow into the carbs from the driver's seat, problem solved!

@ funpig: Are you running an 8V or 16V? If an 8V, what valve cover are you using and is the screen on the PCV port clean and clear?

[rysskii3]

@ rysskii3: Just run a piece of vacuum tubing into the cabin so you can blow into the carbs from the driver's seat, problem solved!

@ funpig: Are you running an 8V or 16V? If an 8V, what valve cover are you using and is the screen on the PCV port clean and clear?

i dont think so.

[funpig]

SAABMAN.. I'm running an 8v with a corrado valve cover and a catch can. No leaking from the top but the bottom end leaks oil like a little MOFO. Getting tired of the spots underneath all the time. Have changed out my seals front and back twice and am looking at changing out my distributor from the 1.8/2.0 combo with TT bushing to the 2.0 with the guts/4window of the 1.8 so that I can seal up the distributor whole better.

[yeayeayea]

IIRC, none of those seals are under any pressure are they? the only oil that hits them should be oil bveing splashed around from the crankshaft or the cams for the distributor.

[funpig]

So heres a pic of my bay. (i know...more whoring)
YEAYEA... there shouldn't be that much pressure but I know on startups my oil pressure gauge hits 100psi for a few blips before it settles down as the motor and oil warm up. same as it has always been on my caddy.

[YJSAABMAN]

Oil pressure numbers at cold start sound right, but OTH yeayeayea is also correct that none of those seals should see that kind of pressure. I'd check the inside of the valve cover to make sure the port is clear and maybe you need a larger hose to the catch can? If you think about it the ABA was designed with the block breather setup, too, and with that blocked off in this application it may need more flow out the top. The hose you have running to the catch can looks much smaller than that PITA plastic tube that runs from the block breather PCV valve on the stock ABA setup.

[rysskii3]

Oil pressure numbers at cold start sound right, but OTH yeayeayea is also correct that none of those seals should see that kind of pressure. I'd check the inside of the valve cover to make sure the port is clear and maybe you need a larger hose to the catch can? If you think about it the ABA was designed with the block breather setup, too, and with that blocked off in this application it may need more flow out the top. The hose you have running to the catch can looks much smaller than that PITA plastic tube that runs from the block breather PCV valve on the stock ABA setup.

i have read that blocking off the block breather is not a good idea. run a hose to the catch can from there.

[funpig]

Thanks guys. I will go ahead and add an additional line to the catch can and probably end up moving it to a new location. let you know how it works.

MikeB