Throttle hookup

bigdreamz2000 · #1 (**permalink**) 10-08-2008, 12:34 PM

I just got my 49cc bike together yesterday. With one exception. My throttle cable is not hooked to anything in the carb. I have the standard carb. How do I hook it up? Right now I just have the cable stuck down the screw cap, then put it through the spring and let it come in contact with the C washer? Does that sound right? Does it just sit down there not attached to anything? I can just pull it out right and it is not locked in place by anything? The directions that came with it do not say anything about hooking the throttle cable to the carb. That does not make sense. Also the throttle did not seem to affect the RPM of the bike. So to experament, I just took out the spring and the C washer. While it was running I pulled up the pin a little and it would idle slower, pull the pin up too much and it would stall. I thought by pulling up on the pin it would increase the fuel or something, guess I was wrong. So by putting the spring back in, it must really be pushing down hard. I don't see how that pin moves at all. I'm really missing something basic here. I'd be glad for some help.

**RedB66** · #2 (**permalink**) 10-08-2008, 01:03 PM

Look here....Motorized Bicycle Carburetor install and rebuild

bigdreamz2000 · #3 (**permalink**) 10-08-2008, 02:30 PM

I looked through the thread but it does not describe how the throttle is linked to the carb. You may have to explain it like I'm an idiot, but I'm willing to take the blow to my ego.

**RedB66** · #4 (**permalink**) 10-08-2008, 03:29 PM

If you take the cap (top) off of the carb, pull out the little cylinder. Look on the underside of it and there's a hole/slot. Hook the end of your cable in there. The spring should hold the assembly together while you insert it back into the carb. There is a pin on the inside of the carb that lines up with the slot in the cylinder. PM me with your number if you can't get it.

bigdreamz2000 · #5 (**permalink**) 10-08-2008, 05:03 PM

I saw that slot. I tried to get the bulb through the slot from the top, and did not know I was supposed to take the sleeve out. I came across great step by step picture instructions at spooky tooth cycle. Which illustrated that you pull the sleeve out, and trap the bulb on the underside of the sleeve's plate. When you slide the sleeve back in, it is trapped underneath. Pulling the throttle lifts the sleeve against the spring. It must be the action of the sleeve that produces more intake and fuel to go to the cylinder. I'll find out when I get home. A benefit to this problem, it led me to seek out information and hence I found this forum. I am amazed at the enthusiasm here, as well as the ingenuity. I may get into this!

**Bikeguy Joe** · #6 (**permalink**) 10-08-2008, 05:05 PM

You will get into this! It's a great source of relaxation, frustration, joy and sorrow.

bigdreamz2000 · #7 (**permalink**) 10-13-2008, 01:13 PM

Throttle has been working great now for about a week with one exception. After a decent ride, >5 minutes, after I pull in the clutch the bike revs up to full RPMs. I can feather the clutch with the break on and the RPMs come back down to normal, or I can back off the idle screw two turns and that seems to have a calming effect on it too. However, with the screw method I have to remember to turn it back in when the RPMs start coming down or it will idle too slow and stall. Any advice why the RPMs have a mind of their own? Thanks!

**Norman** · #8 (**permalink**) 10-13-2008, 05:47 PM

sounds to me like the throttle is sticking or you have an air leak on the intake manifold. if you tighten the top of the carb too much it can cause the throttle slide to stick you might look at that first. I finger tighten the carbs top the spring inside the slide should allow you to open the throttle wide open and when you let go of the throttle it should snap back shut at least that is the way I've always tried to make mine work. There is a lot to things that can make the throttle stick most are in the twistgrip or at the carbs slide sometimes the cable is bent too much or it has a pinched spot or just needs a little lube.

for checking for an airleak spray around the intake manifold to cylinder mount and at the carbs slip on mount if you get a change in rpm when you spray the area with carb cleaner you probably have a leak allowing in air. Look at the classic posts for how to deal with these problems. I like to use silicone on the slip joint and a good grade gasket on the manifold mount.

bigdreamz2000 · #9 (**permalink**) 10-14-2008, 11:53 AM

Good info, can't wait to get home and try that out.