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Vealmonkey
03-22-2010, 10:02 AM
I'm in the process of putting a FCR carb on the 350x. I bought it from a member on the boards hare and it came with a custom intake, carb upgrades and extra bits. I'm putting remote choke cable and remote hot starter cable on the carb and I'm attempting to use the stock trx450r ignition/ light switch, which isn't tested yet. But the question is, what is the hot start cable for or what is its' significance? People ask me, but I don't really know. I was hoping that someone that had a fcr carb on thier bike or quad might be able to chime in here with a really neat answer other than to help start the bike when it's warmed up or warm outside. LOL I know it should just be nice having a more modern, way more adjustable carb that is easy to get parts for, but I would like to be able to give someone and intelligent answer when they ask me what it's for, for a change instead of just shrugging the shoulders! LOL

Racerguy381
03-22-2010, 12:10 PM
The hot start is an Air Bleed, When the engine is hot and you stall it. You pull the hot start lever and 9 times out of 10 it will fire right up. If I recall the Air Bleed is connected right to the float bowl so when you pull the cable it you get fresh fuel directly from the float bowl.

Vealmonkey
03-22-2010, 01:33 PM
So, you don't have to kickstart the engine? I'm not quite following you on this. Sorry.

Racerguy381
03-22-2010, 02:13 PM
Yes you still have to kick start the engine. You just pull the hot start lever on the handle bar or some older models its on the carb. Then kick it over like you normally would and it will fire up. Sometimes you dont even need to used it cause the bike will start without it. Just depends on how hot the engine is when it stalls. When its at running temp which is around 210-220 the fuel gets so hot it boils in the small passages in the carb. When you pull the hot start it will draw fuel directly out of the float chamber making it easier to start. Just remember to not give it any throttle when you are using it, or you will flood the engine.

Vealmonkey
03-22-2010, 04:24 PM
Ahhh, Thank you for explaining that better.

Racerguy381
03-22-2010, 05:56 PM
Anytime! You buy chance wouldnt know anyone with a ATC70 seat or just the seat pan?

honda250sx
03-22-2010, 07:38 PM
atcheaven.com has repro pans I believe...Sry Veal. Just helping out.

Vealmonkey
03-22-2010, 09:05 PM
Nothing to be sorry about, and no your not getting any of my 70 seats! LOL

userj8670
03-22-2010, 09:26 PM
Im sorry but im now really confused with this hot start. You have to pull a cable and then kick it like normal to start it?? why not just start it like normal? You dont need to pull a cable on a warm engine, one kick and they fire up usually. Not trying to be rude but my mind is like a pretzel here lol

Racerguy381
03-22-2010, 10:41 PM
Like I said some engines dont even need it, they start right up without it. I have only needed to use it when I dumped the bike in a corner racing. The bike was so hot at race temp it didnt want to fire, pulled the hot start and it fired right up and away I went. It all depends on the situation, its just a nice thing to have if you ever need to use it.

Vealmonkey
03-22-2010, 10:53 PM
My carb may have come from a crf450r since it had to pull levers mounted directly on the carb and the bikes have more room around the carb. The quads don't and the carb is kind of up inside alot and they use remote cables for the hot start and the choke and that's how I'm running it on my 350x, with remote cables.

audioworks04
03-22-2010, 10:54 PM
I have an FCR on my 450 and couldnt imagine trying to start it when it hot/stalled. I use it any time its up to operating temperature or even just hard starting. Just push the lever and it opens a "plunger" inside the carb allowing in fresh fuel. The staring procedure is no different than normal, just hold the lever open while you kick and it should start easier. Not sure that hot start will do much of anything on a 350x. Hot start is really made for the newer high compression/ high performance motors that are hard to start. I really wouldnt even waste the money the hot start cable and perch I highly doubt that it will do you any good in the long run. How do you set up the remote choke? Is it bar mounted? What machine is it off of or is it a kit that is offered?

Vealmonkey
03-22-2010, 10:57 PM
The remote choke cable is from motion pro. And I'm just using the same 90 degree curved cable end on the choke cable as is stock on the trx450r hot start cable. There is a mount that attaches to the handlebar clamp.

Jason Hall
03-24-2010, 04:03 PM
The hot start Is a air bypass around the throttle slide. It allows only Air around the slide. It give's the engine a burst of air because when the engine shut's off Instantly the cylinder has unburned fuel laying In there. The hot start Is a controlled amount of air to help the bike start without holding the throttle open. Everytime you crack the throttle open on a FCR, you give It a shot of gas from the accelerator pump.

SWIGIN
03-24-2010, 04:54 PM
The hot start Is a air bypass around the throttle slide. It allows only Air around the slide. It give's the engine a burst of air because when the engine shut's off Instantly the cylinder has unburned fuel laying In there. The hot start Is a controlled amount of air to help the bike start without holding the throttle open. Everytime you crack the throttle open on a FCR, you give It a shot of gas from the accelerator pump.

yup, it does NOT shoot fuel into anything. Think of it as the opposite of a choke.

Most times you will never need it on a 350x unless it is flooded. If it's flooded you can pull the hot start and kick it over a few times to dry out the cylinder. A huge big bore stroker 350x motor does need a hot start though.

Racerguy381
03-24-2010, 05:53 PM
Sorry about the miss comunication on my part. I knew it was an air bleed but wasnt aware that it didnt give the engine fuel at the same time. Thanks for correcting my information. At least I have the procedure for how to use it correct.