Kehin's On The X
- Thread starter Rupunzell
- Start date
Robert Mose
True Classic
Nice!
Nice setup. Did you make the manifold?
Nice setup. Did you make the manifold?
The manifold is made by an aluminium fabrication company here in the UK. My welding skills are pretty shoddy so I left it to the experts!
First Start...
[ame="http://www.youtube.com/watch?v=I9uILzbrQr8"]YouTube - Fiat X1/9 walkaround. ZX6R Bike Carbs, Megajolt, Etc[/ame]
And the Sound! :shock:
[ame="http://www.youtube.com/watch?v=FaDSuYt55l0"]YouTube - Fiat X1/9 Test Drive[/ame]
I now wish I had got the manifold made a little longer as the torque is fairly low...
Iain
First Start...
[ame="http://www.youtube.com/watch?v=I9uILzbrQr8"]YouTube - Fiat X1/9 walkaround. ZX6R Bike Carbs, Megajolt, Etc[/ame]
And the Sound! :shock:
[ame="http://www.youtube.com/watch?v=FaDSuYt55l0"]YouTube - Fiat X1/9 Test Drive[/ame]
I now wish I had got the manifold made a little longer as the torque is fairly low...
Iain
Rupunzell
Bernice Loui
These are 36mm Kehins
which should be good enough for the LeMons car. They were a bargain, about $100 USD and the supply is pretty good and fits the LeMons budget. Chris got them from a motor bike shop.
The runners are tuned for a torque peak of nee 5,000 RPM. Since these are constant velocity carbs, they are similar to a "standard carb" with a 36mm choke.
We got a lot of tuning to do once these are installed and set up.
What are the results of using "bike carbs" on your X so far?
which should be good enough for the LeMons car. They were a bargain, about $100 USD and the supply is pretty good and fits the LeMons budget. Chris got them from a motor bike shop.
The runners are tuned for a torque peak of nee 5,000 RPM. Since these are constant velocity carbs, they are similar to a "standard carb" with a 36mm choke.
We got a lot of tuning to do once these are installed and set up.
What are the results of using "bike carbs" on your X so far?
kite63
True Classic
Mine worked GREAT from the word go. Once I got the intake manifold right, they got even better. Mine were a little rich overall from the start, but I had the angle wrong. The FCR's are pretty sensitive as to the angle at which they are installed. They will work at pretty much any angle that is close, but are designed to operate at the SPECIFIC angle at which they would be if on the bike. Get this part RIGHT.
These currently on the car are downdrafts and required a bend in the intake runner to get to the appropirate angle. They fit under the stock engine lid and within the engine bay. I am planning another setup useing FCR sidedrafts that will hopfully result in an intake runner having a staight shot to the head. But this will most likley require cutting into the trunk/crossmember area.
Later, Kelvin
These currently on the car are downdrafts and required a bend in the intake runner to get to the appropirate angle. They fit under the stock engine lid and within the engine bay. I am planning another setup useing FCR sidedrafts that will hopfully result in an intake runner having a staight shot to the head. But this will most likley require cutting into the trunk/crossmember area.
Later, Kelvin
They reinstalled your steering wheel on the wrong side when they built the manifold. I'd talk to them about that.
:nana:
Sounds great!
details and questions
Our Lemons X carbs are 36mm CVK's.
Question for folks that have them running properly - what ballpark main jetting do you use? We're jetted at 155s now, and I want to order up a jet kit that has some sizes in-around where we think we will be for fine-tuning. But would like to order jets centered around where we think we'll need to run. So what jetting (again roughly) are you guys running on Keihins?
And what fuel pressure are you running? I'm seeing posts of anywhere from 2.5 to 4.5 psi. Seems like shots in the dark so far. Pointers appreciated.
Our Lemons X carbs are 36mm CVK's.
Question for folks that have them running properly - what ballpark main jetting do you use? We're jetted at 155s now, and I want to order up a jet kit that has some sizes in-around where we think we will be for fine-tuning. But would like to order jets centered around where we think we'll need to run. So what jetting (again roughly) are you guys running on Keihins?
And what fuel pressure are you running? I'm seeing posts of anywhere from 2.5 to 4.5 psi. Seems like shots in the dark so far. Pointers appreciated.
My carbs are overfueled right now and from memory they are 160 main jets but don't quote me on that. Of course it all depends on the climate, fuel, etc...
I have heard of some guys buying a set of micro drills and drilling out the original jets in tiny increments until they get the right size, maybe that would be the answer...
What kind of fuel pump are you using?
I have a self regulating pump which came off the same bike (ZX6R) and it cost me £20. All it needs is a 12V feed; no return, no pressure regulator, no hassle! I believe most bike pumps run at around 3psi but I guess it depends on the carbs in question.
Get yourself on ebay and just buy a bike pump.
My carbs were £9.99
My pump was £20 and it came with a free set of carbs to be used for spares
I have heard of some guys buying a set of micro drills and drilling out the original jets in tiny increments until they get the right size, maybe that would be the answer...
What kind of fuel pump are you using?
I have a self regulating pump which came off the same bike (ZX6R) and it cost me £20. All it needs is a 12V feed; no return, no pressure regulator, no hassle! I believe most bike pumps run at around 3psi but I guess it depends on the carbs in question.
Get yourself on ebay and just buy a bike pump.
My carbs were £9.99
My pump was £20 and it came with a free set of carbs to be used for spares
fuel pump
We've got a Holley pump in there now - it's massive. But it's on a return style pressure regulator, so fuel flow won't be a concern (too much fuel, actually, is a concern).
Thanks re. the tip on jet sizing. Bike Bandit has jet kits for about $22/ea (I think I need to buy 4x because there are 4 of those puppies). They have two kits, one centered around 155 (150-160 in ~.2mm increments) and one centered around 165 (160-170 in ~.2mm increments).
The larger kit seems like a winner, but, if you're over fueled at 165, then maybe I need to scale back. Or, let's get it running, and see what we see.
I've done the calibrated drill before on some Weber jets, and that works too...so long as you're going UP in size. Going down, not so much.
We've got a Holley pump in there now - it's massive. But it's on a return style pressure regulator, so fuel flow won't be a concern (too much fuel, actually, is a concern).
Thanks re. the tip on jet sizing. Bike Bandit has jet kits for about $22/ea (I think I need to buy 4x because there are 4 of those puppies). They have two kits, one centered around 155 (150-160 in ~.2mm increments) and one centered around 165 (160-170 in ~.2mm increments).
The larger kit seems like a winner, but, if you're over fueled at 165, then maybe I need to scale back. Or, let's get it running, and see what we see.
I've done the calibrated drill before on some Weber jets, and that works too...so long as you're going UP in size. Going down, not so much.
I don't know about your carbs but mine have an idle mixture control on the bottom of each 'barrel'. The guys who made my manifold (and knew what they were doing concerning bike carbs) turned each of them out a few turns and they said to have a play around with them to find the right mixture. I THINK turning them out made it richer but it has been so long since I did it!!
Please let me know the results of your tests as although my car is drivable (and sounds unholy), I could make it sweeter...
Iain
Please let me know the results of your tests as although my car is drivable (and sounds unholy), I could make it sweeter...
Iain
kite63
True Classic
I have #165 mains in my FCR's now. They came with #160 and I have a set of #170 that I have tried. The #170 seemed a bit rich but still ran well, the #160 seem to work a little better in really hot weather. All this is according to the butt-dyno, which may or may not be confirmed if I ever get it on a real dyno. The air screw is mostly for fine tuning idle, and has no real effect beyond 1/4 throttle. I never wrote down the #'s for the pilot and air jets, they are as supplied from manufacturer.
Later, Kelvin
Later, Kelvin
Working now
[ame="http://www.youtube.com/watch?v=u-EPBibaHks"]YouTube - Lemons Fiat X1/9 Motorcycle Carb Test 2[/ame]
We have 180s in it now, and may have to go 185s to carry the top-end. The bigger main jet will cause the middle to go all boggy, but a fatter needle taper will lean out the midrange to offset. We're thinking of changing the head, and I don't want to put a lot of time into setting up this carb configuration beyond what's here as it will all change if we put a different head on it.
[ame="http://www.youtube.com/watch?v=u-EPBibaHks"]YouTube - Lemons Fiat X1/9 Motorcycle Carb Test 2[/ame]
We have 180s in it now, and may have to go 185s to carry the top-end. The bigger main jet will cause the middle to go all boggy, but a fatter needle taper will lean out the midrange to offset. We're thinking of changing the head, and I don't want to put a lot of time into setting up this carb configuration beyond what's here as it will all change if we put a different head on it.
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