stumped

[jp8400ex]

I can't figure this one out... My 406ex w/10.6 comp, hotcam stg2, uni filter, no airlid, stock exhaust, 14 tooth front sprocket, and jetted stock carb will not outrun my buddy's stock 400ex in a 200 yd drag race! I am still running stock tires while he has razrs. Could tires create that much of a difference? Could my choice of cam combined with stock exhaust cause me to lose power? Maybe my 14 tooth is too low geared for my setup? Is the stock clutch holding me back? Or do I possibly just suck at drag racing? Any opinions are welcome.

[throwinitup]

did you build your bike or buy it...be honest...cuz if u bought it, you prolly got ripped off

[mojoe2878]

a good exhaust would help compliment the mods that you have a lot. if your buddy has smaller rear tires its helping him out alot on acceleration.
regardless of the mods you have it will still depend on the rider of each machine, racing is about 80% rider and 20% machine. a fast quad wont do you much good if you dont run it right.

[DaleJrFan]

is he getting you off the line or just out running you through the gears? having a 14t front sprocket you are going to lose some of your top end so if he is pulling ahead of you in 4th and 5th, that is your prob.

[jp8400ex]

I built the 406 myself using a service manual as my guide. Don't get me wrong, my bike runs great. The race is very close from start to finish. I just expected my 406 to perform a little better.

[Honda5]

I have a 400 like yours with a t-4 full exhaust and it rips but, when I put my stock exhaust back on for a "quiet" ride I could not get out of my own way and was getting spanked by alot of lesser bikes. So the answer is yes it is your exhaust.

[cals400ex]

you should be eating him. if you are getting beat from 3-5th gear, i would run stock gearing. also, adjust your throttle cable. make sure there isn't more than 1/4 inch of slack in the cable. it will make a huge difference if there is. also, what jetting you running?

[jp8400ex]

155 main, 45 pilot at 1400ft altitude. 45 to much? Seems to start and run ok. I think maybe the stg 2 cam just doesn't compliment my current setup. Might get stg 1 or hrc. Any ideas?

[04'400ex'er]

Originally posted by jp8400ex
155 main, 45 pilot at 1400ft altitude. 45 to much? Seems to start and run ok. I think maybe the stg 2 cam just doesn't compliment my current setup. Might get stg 1 or hrc. Any ideas? If your considering getting a different cam because it dosen't compliment the stock exhaust well, then why not just get a new exhaust?:huh

[cals400ex]

i found a 45 pilot to work just fine. all you need to do is turn your fuel screw in a bit. this is the essentially the same as a 42 pilot jet with the fuel screw out a little bit.

if your running a stock pipe because you need it quiet, i respect that. i modded my stock exhaust and you can do that too if you need it quiet. i drilled some large holes in my muffler behind the spark arrestor. i didn't mod the spark arrestor though. with the spark arrestor on, you should not notice a difference in noise. also, you can grind the welds down in the front of your headers to free up a bit of flow. your jetting doesn't seem bad. a stage 1 or hrc might suit your setup a little better. i would really consider one of those because of the stock pipe. also, i want you to check your thorttle cable. that can make a huge difference.

[jp8400ex]

I feel stupid now. my throttle cable had almost an inch of play!! I forgot to readjust it when I put my motor back together. That means I was dead even with my buddy's quad in a drag race using only 3/4 throttle!! Goes to show you how important the little things are. I can't wait to take my 406 out for a test drive. Thanks for the advice cal!

[bdrue]

haha thats funny....put a pipe on that thing too

[cals400ex]

i see that all the time. it makes a huge difference. when i tested it, i gained 5mph on a road according to a truck speedometer. 5mph doesn't seem like a lot but it is huge.