I recently put a new top end on my 400ex and I was wondering if it is normal for it to sound deeper while its running? They put a weisco piston in it and I believe it was a .20 size bigger, I wanted to keep it as close to stock as possible.
Anyways while I was breaking it in I noticed that it sounded a little deeper, almost as if I had taken the air box lid off. I was curoius so I took the end cap off the stock exhaust to see if something was broken. Now for the question? Is ther sapposed to be packing around the spark arrester part of the end cap???
any help would be appreciated,
thanks

 

Packing goes every where, it might sound deeper because you forgot to connect the carb to the airbox or the airbox lid is off. As for packing/arrestor, take it out and leave it out, it just craps up anyway.

 

I didnt do the work but I did check all the connections from the carb. everthing was tight.
and the airbox lid was on, what I was saying is that it sounded like the lid was off.

 

Does anyone else have any suggestions?
Dan250r thanks for your input but but what you mentioned didnt seem to be the prob.

 

check all your exhaust connections, something could be loose and causing a leak

 

Make sure the headpipe seals have been replaced with new ones.

 

is it just a deeper sound? what compression piston did they put back in? I think the baseline piston from wiseco has a higher compression than a stock honda piston. no the packing doesn't go in with the spark arrester. the packing in the stock muffler can only be seen if you cut the pipe open. [img]i/expressions/face-icon-small-cool.gif[/img]

 

thanks for all the info, Ill check the head pipe seals, and if thats not it Ill call theguy to see if it was a high compression piston.
Thanks again