Best Rev Box?

I see so many different brands and types of rex boxes, and ill be getting one soon, so which one is the best? I heard some there they takegawa was worth buying

none are worth the money but kitaco gets the popular vote

trailbikes coming in a close 2nd because it isnt so danm expensive!

There is a write up on another site. Yet to be completed. But basically speaking, if you have a stock low compression motor , or anything modified with low compression, then you wont notice anything. The only thing you will notice is the rev limiter is lifted, or set higher, depending on which box you choose. Your timing may be affected a little, but I think for the most part that you wont notice anything. I have a kitaco and can say when we installed it on our 70 motor it didnt do anything at all. It was a stock compression motor though. Even with port work and a cam , I didnt notice any difference between the stock one and the aftermarket.

For me, I would say unless you have a die hard setup motor, just plugging in a cdi box is a waste of money on a stock or mild modified motor.

i got a bbr one on my stock 02 xr70 and it seemed to make the motor wind out more. maybe not worth the 50 bucks though

i got a bbr one on my stock 02 xr70 and it seemed to make the motor wind out more. maybe not worth the 50 bucks though

I would think that the reason ( or what you noticed ) was lack of rev limiter. Whether it was truely making any more power wouldnt be noticed unless you threw it up on a dyno. While it may feel faster I would doubt it was really faster. Basically more noise and rpm always make things feel faster.

As I noticed the same thing on ours as you did. It would wind out more, but when it was raced at the drag strip, it made no et or mph difference between the stock cdi and our kitaco. Not saying that the BBR might not have made a difference though.

Which I think as you say, for the $50 I dont think it was really worth the difference in rpm limiter or lack of.

the timing curve on the stock box starts to kill the power at around 9500 rpm, no "limiter" on the stock cdi. the cam, valve springs, ect.. also limit the motor to about 9500 rpm.

you will get better throttle responce because the box' do slightly advance the timing, and maybe a few more rpm.

aka jack schitt

the timing curve on the stock box starts to kill the power at around 9500 rpm, no "limiter" on the stock cdi. the cam, valve springs, ect.. also limit the motor to about 9500 rpm.

you will get better throttle responce because the box' do slightly advance the timing, and maybe a few more rpm.

aka jack schitt

yep... unless you're running a 88 race head that's been worked over, big exhaust, big carb, Inner rotor kit with the clutch moved off the're not going to notice anything but a little better throttle responce.....

the bigger piston actaully woin't rev out as high as teh stock 50 piston in most cases ( more mass to move = slower)............. we have 2 88 race head bikes.. one has a big pipe and a stock rev box ( new style race head ).. it won't hit the stock limiter and won't rev any higher than the other one

the other one.. ( my personal bike ) has an old style race head on a stock pipe and a TB rev box... the only dfference is that the one with the TB box responds just a little faster on the initial throttle opening

both are running 20mm carbs jetted perfectly for their setups, adn both are running teh same cam ( stage 2 style.,.. a.k.a...the old race head cam)

liek fiveo said...even if you do get teh bike revved out that far, valve float start to make it run like ish anyway ... i got minebecause itwas 24 bucks adn it was shiny ( plus i didn't know anybetter at teh time )

rev boxes are only really good for highly modified motors. Tokyo Mods is one of the better boxes, but Trail Bikes rev is supposed to be pretty good and dosen't cost so much.

you'll notice more from a coil than a rev box. I think they are a gimmick if you ask me but I still buy em..haha. Tokyomods full setup is really the only one that probably actually does something.

Now on my end. my 117cc will not run on a stock CDI. I smoked a aftermarket one so I replaced it with the stock one and the bike felt like it lost half it's power and we did not race it the rest of the day. Now my bike likes to run at 13k so the stock will have it's limits. save your $40 and have the flywheel drop some LBS. stock trim a good bang for the buck.

theres no way the flywheel can even lose 1lb, and even if that doesnt help at all. you may feel the rpm climb and drop a bit faster, if u have a manual clutch.

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