dragging problem

[400eXr1d3rZ]

when i try to start in second gear to drag, and i pop the clutch it sounds almost like im starting in 5th gear, is this a normal issue? would it be fixed by dropping a tooth in the front spocket it? i just dont want to loose alot of top speed, but i want alot of accell.

[Scro]

If dropping a tooth on the front is too much for you, add a tooth to the rear. It will gear it down just a hair, but won't take away much on top end.

[400eXr1d3rZ]

wont I need a new chain if i add on the rear? how much would i notice?

[400exrules]

just learn to start in first. Dumpin it in 2nd is not only relaly slow, but a very bad idea.

you will be 10 times faster if you just practice and learn to start in first

[Scro]

Originally posted by 400eXr1d3rZ
wont I need a new chain if i add on the rear? how much would i notice?

You should have enough adjustment in the carrier not to replace the chain. It may the difference between being able to start in second or not;)


Originally posted by 400exrules
just learn to start in first. Dumpin it in 2nd is not only relaly slow, but a very bad idea.

you will be 10 times faster if you just practice and learn to start in first

If you can get it to spin, you are much better off starting in second. If you can't (i.e. on pavement), it's better to start in first.

[400eXr1d3rZ]

i keep forgetting that im getting a 416 10.8:1 piston kit, would that make up for the loss of top speed from dropping a tooth on the front sprocket?

[exrider008]

Originally posted by 400eXr1d3rZ
i keep forgetting that im getting a 416 10.8:1 piston kit, would that make up for the loss of top speed from dropping a tooth on the front sprocket?

that dosnt really give u top end but with that u wont have to gear in down cuz of the added power.

[hondamanex400]

Originally posted by 400eXr1d3rZ
i keep forgetting that im getting a 416 10.8:1 piston kit, would that make up for the loss of top speed from dropping a tooth on the front sprocket?

Why spend the money on a 10.8:1 piston, when for the same amount you can get a 11:1 compression? You will still be able to run 93 octane that can be obtained at almost any gas station. The higher the compression, the more power all around.

Also, are you doing organized drag's or just you and your buddies? Cuz if your doing organized, then your going to want to strap both front shocks and the rear shock all the way down. this will stop you from wheeling off the line or in any gear. I have tried to do second gear take offs for draging, and found that I ran quicker when I just took off in first gear.

This is just my .02 cents though.

[400eXr1d3rZ]

its not organized dragging, at the dunes i went to had a drag spot and got "smoothed" every 15 minutes by the owner of the land. one day i hope to build a full drag quad though.

someone said that i had to mix 50/50 with a 11:1 piston, whats the difference in hp from a 10:1 and 11:1.


EDIT: won't i have a heat problem? what can i do to keep my bike cool while im riding?

[GPracer2500]

Originally posted by hondamanex400
Why spend the money on a 10.8:1 piston, when for the same amount you can get a 11:1 compression? You will still be able to run 93 octane that can be obtained at almost any gas station. The higher the compression, the more power all around...

I think you'll find a JE 10.8:1 pumps just as much as a Wiseco 11.0:1. I haven't actually tested that but Wiseco's do have a reputation for not quite pumping to expectations [shrug].

This is why I believe this is the case: Both Wiseco and JE use the same pistons for the XR400R and the TRX400EX. The EX has a stock compression ratio of 9.1:1. The XR has a stock compression ratio of 9.3:1 (because of different gaskets). Notice the difference is the same .2 points between Wiseco's 11:1 and JE's 10.8:1.

JE uses EX specs to list many of their XR/EX pistons while Wiseco uses XR specs to list their XR/EX pistons. Just remember that those figures are not the final word on what the actual dynamic compression of the engine will wind up being. As shown above, just a change in gaskets is going to push the numbers one way or the other. There's a whole host of things that determine the dynamic compression of an engine (as appossed to static compression) and dynamic compression is what really matters.

BTW, I've got a JE 10.8:1 and must run a race/pump mix for anything but mild riding. With my gaskets, cam, riding environment, etc. that's just the way it turned out.

[400eXr1d3rZ]

If I was to get 11:1 piston could I still run 93 pump gas?

[Honda2000]

Yes, depends upon where you live. Race fuels will help your motor stay cooler.

[400eXr1d3rZ]

Where I live they have 93 octane everywhere, would my motor run hot if i just ran 93?

[400exrules]

it might, it might not, it would be safer to run a 1:5 ratio of race gas:93.....but you will just have to see how YOUR bike does with an 11:1

[okbeast]

Why not run alcohol? :D Well that's what I plan on doing to keep mine running cool.

[400eXr1d3rZ]

Originally posted by okbeast
Why not run alcohol? :D Well that's what I plan on doing to keep mine running cool.

That kit costs ALOT, for a predator it is like 2000!!!

[okbeast]

I'm pretty sure they have different carbs tho. If you have FCR carbs....which will bolt up to the 400ex's, then the kits aren't that bad.

Learn to feather the clutch.

Release the clutch in such a manner as to keep revs high. You'll get a little bit of "dragging" until you get good at it.

I never got good starts in first gear.

The only reason I didn't get the holeshot using second gear is I lacked the stones.

This was on a 250R with intake and exhaust mods, but no motor mods.