Sparks Timing advance???

[frenimy]

I have a Sparks Timing advance that I want to install but I also have a rev box. Are there any issues when using both? I believe the rev box is just the XR400 box as it came with the quad. I am also curious to know how the timing advance would work with a stage 1 hotcam. Thanks in advance for your input.

[hornetgod13]

There are 2 types of aftermarket CDI boxes. One just raises the rev limiter and the other advances the timing and raises the rev limiter. With the advance timing key you should only use the one that just raises the rev limiter. What brand Rev Box do you have?

You can use the hotcam and timing key together. The timing key is not to be used on oversized higher compression pistons

[frenimy]

So then I should not install it if I plan on doing a 416 kit in the next month or so

[TURBO-530R]

you can install it i ran one in my 12 to 1 508 for years

[oleboy87]

yep that is correct! i wouldn't if you plan on going hi compression piston in the future

[frenimy]

So just curious what are the reason behind you guys saying that is doesn't work. How does the High comp affect the advance key?

[08400EX]

Originally posted by frenimy
So just curious what are the reason behind you guys saying that is doesn't work. How does the High comp affect the advance key?

High Compression pistons increase the chances of pre-detonation (knocking), that is why you have to run a high octane fuel. Most people don't know it, but the higher the octance the slower the burn, hence less chance of pre-detonation.

Advancing timing can also cause pre-detonation, so adding 2 devices that are prone to pre-detonation can yield bad results... unless you are very careful and know how to tune around it AND always use a consistant high octane fuel.

[TURBO-530R]

I ran fuel

[08400EX]

Originally posted by TURBO-530R
I ran fuel

Don't we all :-)

What octane did you use?

[TURBO-530R]

vp-112 in that bike

[08400EX]

Originally posted by TURBO-530R
vp-112 in that bike

Wise choice !! http://www.exriders.com/vbb/images/icons/icon14.gif

[JOEX]

Originally posted by TURBO-530R
you can install it i ran one in my 12 to 1 508 for years

Originally posted by TURBO-530R
I ran fuel

Originally posted by TURBO-530R
vp-112 in that bike
Thanks for sharing all the details:rolleyes:

[81 clark racing]

not to steal your thread or anything but i was told i could not run an after market rev box on my 400ex because i have the sparks adv timeing key.....i have a full procircuit pipe, uni air filter, modified air box, icat spark enhancer, stage 2 hot cam and the timeing key. do you guys think id be ok runing a aftermarket rev box? if so what kind? im worried im going to get pre det tho thats y i never ran and aftermarket one. i also run a 50/50 mix cam2 ( 110 octane) and 93