need advice my 07 450r barely outruns a 06 Dvx 400

[coltrain65]

need to know what the deal is here, and what i need to do in order to fix it your advice would be appreciated.
i have a 170 main jet, 45 pilot, air lid off, and baffle out of the exhaust. i live in missouri. and it also dies if i pull the clutch in and cost to a stop after wide open throttle. need advice please.

the dvx is pure stock
please tell me why my 450 barely outruns it.
thanks

[strokerinc83]

Check valves/ And a 170 main? Im running a 170 main with 14:1 Compression, portwork,cam and intake. Might be a little rich.

[chevys&honda$]

ltz/kfx/dvx 400's are pretty fast even stock, i have both z400/450r, before i put the cam and re-jetted the 450r the 400 would run right with it....

[coryatver]

you should destroy a dvx400 it isn't even close. I would say something is way out of tune

[Chino886]

coltrain, sounds like you are way too fat up top. I would say drop down to a 162-168 for you here in MO. I just built a 06 head that pulled 53/35 on a dyno and it ended up needing a 172 with 14:1 piston, aftermarket intake and cam.

[Baileygunns]

Way to fat on the main jet... An 04/05 with the mods you've done should be around a 170 maaaaaybe a litle more.

[airmobile101]

Yep, way to rich. I run a HRC cam and a full LTE exhaust and Im only at 165. My DVX400 would walk all over my 450r when the 450 was bone stock. Its a different story now with the mods to the 450;)

[coltrain65]

when i got the 450 it would hesitate whenever i would punch the throttle in 4th and 5th that was on the stock main jet so i jumped up to a 150 main it got rid of the hesitation, but then the dvx was outrunning it so that's when i went to the 170 then i was winning however even on the 150 main if i go from full throttle and pull in the clutch it floods out. Does getting an exhaust make that much difference in these things, in order to get ahead of the 400's?

[airmobile101]

How do you know that the DVX400 is stock?

[chevys&honda$]

Originally posted by coltrain65
when i got the 450 it would hesitate whenever i would punch the throttle in 4th and 5th that was on the stock main jet so i jumped up to a 150 main it got rid of the hesitation, but then the dvx was outrunning it so that's when i went to the 170 then i was winning however even on the 150 main if i go from full throttle and pull in the clutch it floods out. Does getting an exhaust make that much difference in these things, in order to get ahead of the 400's?


sounds like you needs to go down a little on the main jet and go UP on the LEAK jet, the small leak jet is causing the hesitation....

[coltrain65]

it's one of my buddies and he hasn't done anything but wreck it a couple of times lol.

[coltrain65]

not sure if i know what you mean by the leak jet. i went to a 45 on the pilot and i pulled out the needle but it wasn't adjustable, i have heard about adjusting the fuel screw but not even sure where it's located on the carb.

[chevys&honda$]

Originally posted by coltrain65
not sure if i know what you mean by the leak jet. i went to a 45 on the pilot and i pulled out the needle but it wasn't adjustable, i have heard about adjusting the fuel screw but not even sure where it's located on the carb.



the leak jet is in the float bowl, i dont remember what the stock size is but i think i went to a #50 leak jet and the bog/hesitation cleared up...

you should PM d3ktrix, he always has the right answers as far as 450r's and jetting........

or do a search on leak jet or jetting there is tons of treads on this stuff.

[Pack]

It's because it's a Honda.

Yamaha > Honda

[airmobile101]

Originally posted by chevys&honda$
the leak jet is in the float bowl, i dont remember what the stock size is but i think i went to a #50 leak jet and the bog/hesitation cleared up...

you should PM d3ktrix, he always has the right answers as far as 450r's and jetting........

or do a search on leak jet or jetting there is tons of treads on this stuff.
Im thinking its a 70 leak jet stock. I went with a 55 leak,but I know I could use a 50 as well.

[coltrain65]

so going down on the leak jet makes the hesitation go away? that seems weird. What site do you get those from?

[strokerinc83]

I got mine in a HRC jet kit. I got the kit for the needle and the leak jet.

[redrider74]

stock leak is a 70.. go down to a 55 and the hesitation should go away..

you can get one here..

http://www.magicracing.com/Keihin-FCR-Acce...p_717-1603.html

[coltrain65]

i also just noticed that these 07's have a 13 tooth front sproket what kinda mph gain will i recieve by going to a 14 in the front.