Fitted in what type of frame?

 

crf type frame

 

Hi all



Does any one run one of these will i gain much over my vm 26 are they hard to set up? any pics with one fitted ?



i am building a yx 140 moter with a 160 tb kit on and a takegawa super head +r and a s35d cam

You aren't gonna get any more power with that carb because even though they list it as a 28, it's more like a 26mm carb.

You'll have to make a manifold for it and depending which CRF frame you are using, yo

u'll run into clearance issues.

 

not enough fuel for the bike, results in almost a loss in power. plus like dood said the hassle of making an intake

 

The carb is hard to setup but once you get it right it will give you more than the VM26. That's not opinion. The FCR is a true 28. I'm not a dealer or a vendor I just check my facts over and over and over.

 

who puts a 400$ carb on a 200$ engine at:

 

The carb is hard to setup but once you get it right it will give you more than the VM26. That's not opinion. The FCR is a true 28. I'm not a dealer or a vendor I just check my facts over and over and over.

While its great that you check your facts. The fact is,

I've had them in my hand and actually bored them.



Starting size is 25.5 from where the slide is. 28.2 at the spigot.

 

 

Then you have a 26 not a 28 which they make both of. If you don't think so check Sudco.

 

You aren't gonna get any more power with that carb because even though they list it as a 28, it's more like a 26mm carb.

You'll have to make a manifold for it and depending which CRF frame you are using, yo

u'll run into clearance issues.

Ive read you say that about the FCR 28 a few times now, and I dont understand what you mean? Mine is 28mm straight through



And if you buy the Kitaco kit it bolts right on, no need for a custom manifold



It is very tight fit on a CRF frame though!

 

Then you have a 26 not a 28 which they make both of. If you don't think so check Sudco.

I know he is very knowledgeable about engine building, but in this case he either had a different carb or his v-caliper is broken or out of calibration...



I just took these pictures right now, and mine is 28mm+ straight through

And here is a pic of the tight fit in an aftermarket CRF50 frame

 

Yes sir my fcr is a true 28mm carb. Measured 28.47(no boring or anything) a the inlet side and 27.89 at the spigot side.

 

Hey JonnyP what size jets are you running in your fcr? Main and pilot?

 

Hey JonnyP what size jets are you running in your fcr? Main and pilot?

Im still using what came in it with the Kitaco kit, it ran so well right out of the box on my 124+R I havent made any jetting changes....I dont race so top performance isnt too important, but I do plan to have it jetted/dyno tuned when I get my head back from porting...



Pilot #45

Main #108

 

Im still using what came in it with the Kitaco kit, it ran so well right out of the box on my 124+R I havent made any jetting changes....I dont race so top performance isnt too important, but I do plan to have it jetted/dyno tuned when I get my head back from porting...



Pilot #45

Main #108

Ok thanks.

 

Ok thanks.

Also you can see the red anodized bowl on the accel pump, that is an adjustable leak jet I just added...This allows you to adjust the amount of accel pump squirt without making jetting changes...Cant wait to try it, will make tuning the accel pump easy

 

Then you have a 26 not a 28 which they make both of. If you don't think so check Sudco.

When I worked at BBR and tested almost every carb out there for different applications. The 28 is what we ordered.

I know they make a 26 and is closer to a 24 carb.



It uses the same carb body and slide. Just different hole in the center.





hehe.... I said hole in the center

 

Also you can see the red anodized bowl on the accel pump, that is an adjustable leak jet I just added...This allows you to adjust the amount of accel pump squirt without making jetting changes...Cant wait to try it, will make tuning the accel pump easy

I was thinking about the accel pump.But i didn't use my fcr much to go and invest in one.I only used it maybe 5x's,i couldn't tune it to many things to mess with.Lol

When I worked at BBR and tested almost every carb out there for different applications. The 28 is what we ordered.

I know they make a 26 and is closer to a 24 carb.



It uses the same carb body and slide. Just different hole in the center.





hehe.... I said hole in the center

probably sent out a bad batch and the customers started complaining that it wasn't a true 28mm or something. When i got minds the first thing i did was measure it.I thought it looked kinda small at the opening for a 28mm.

 

where did you get your carb mount from jonnyp? it looks well on your bike

 

where did you get your carb mount from jonnyp? it looks well on your bike

It came with the Kitaco FCR 28 kit, they offer 2 kits....One has 2 cables (push/pull) and the one I have with one pull cable....Both kits come with the carb, velocity stack, mounting boot, cable/cables, and a plastic throttle...

 

Is it worth the money to buy adjustable acceleration pump cover? What do you think?



And Iam thinking about getting gasket and air filter bracket fitting instead of the red velocity stack. I plan to use the carb in my supermoto, but I want some protection aginst dust and other... I know, that motorcyclecarbs.com are selling this things, but I heard about them, that they are not good to deal with. Do you know someone else who is selling this?



Here are the links...

FCR / FCR-MX O-RING / RAM ADAPTER



http://www.motorcyclecarbs.com/Keihin_FCR_FCR-MX_Airbox_Ada_C1608.cfm



Keihin FCR-MX R&D Racing Power Pump

 

Is it worth the money to buy adjustable acceleration pump cover? What do you think?



And Iam thinking about getting gasket and air filter bracket fitting instead of the red velocity stack. I plan to use the carb in my supermoto, but I want some protection aginst dust and other... I know, that motorcyclecarbs.com are selling this things, but I heard about them, that they are not good to deal with. Do you know someone else who is selling this?



Here are the links...

FCR / FCR-MX O-RING / RAM ADAPTER



http://www.motorcyclecarbs.com/Keihin_FCR_FCR-MX_Airbox_Ada_C1608.cfm



Keihin FCR-MX R&D Racing Power Pump

Dont buy anything from Motorcyclecarbs.com! I just wasted $75 with them ordering that exact same gasket, and an air filter adapter. They have them listed for all FCR carbs but those are all too big, both the gasket and the adapter they sent me are too big and dont fit the FCR28.



I had to special order the correct size FCR adapter from a Sudco dealer, I found out there is only one that actually fits the FCR 28 (part # 021-211)..For the gasket Im using an Oring that is close to the right size....

Im going to make my own filter for it out of some screen and an old UNI filter...



As for the adjustable accelerator pump cover, IMO its great because without it the only way to control the amount of squirt is by changing the jetting...Which can be a pain in the ass, even if your jetting is close you could have a bog due to the squirt...Now I can adjust just the squirt without touching the jetting...They are expensive thou! Mine is the R&D one you posted but I payed a little more for a red one, those sliver ones are a little cheaper because they are raw aluminum not anodized



Ive seen some people make it adjustable by adding a home made set screw setup on the rod that pushes the diaphragm, so you can limit its travel...

 

I need some help from you guys with the 28mm Keihin FCR Downdraft Carburetor. Can you guide me in the right direction on the following questions listed bellow -

Jetting - I need a jetting starting point?

Engine Information -
*General - Custom Built 184cc Electric Start w/ Back Up Kick Start Big Bore Stoker Engine built by Pitster Pro "USA Motor Toy's LLC" in there Race Engine Program.
*Displacement - 184cc
*Port/Polish - Withrow Powersport's WPR Aggressive MX Port/Polish
*Head - TB V2 Roller Race Head
*Cam- Custom Race Grind/Profile done by Pitster Pro
*Valves - Custom Titanium Valves --- Intake 28.5mm --- Exhaust 23.5mm
*Springs/Retainers - ZS Heavy Duty Racing Valve Springs w/ Ti Retainers
*Piston - 13.5:1 High Compression Pro-Lite Cast Aluminum Piston
*Crankshaft - Long Rod Stroker Crank
*Stud Kit - Kitaco Forged Cylinder Stud Kit
*Exhaust - FMF 4.1 Titanium Exhaust System (Big Bore CRF-50/70)
*Carburetor - 28mm Keihin FCR Downdraft
*Ignition - Dynatek Programmable Digital 4-Curve CDI Box w/ custom timing curves (TRX-400EX), Dynatek Miniature Series Coil (TRX-450R), Accel 8.8mm Spark Plug Wire, NGK-IX Iridium Spark Plug, Lightweight Flywheel,
High Output Stator, & Mini 6-Cell Lightweight Lithium Battery
*Air Filter - K&N Filter w/ Outerwears Pre Filter
*Timing Chain - Kitaco Heavy Duty Timing Chain
*Clutch - 4spd Manual HD Clutch Kit, Billet Clutch Basket & Rekluse Z-Start Style Sport/Auto Clutch


Please help me out on a starting point for the jetting, It would help me out a lot.

Thanks,
Jim