Hi Guys,
I'm pretty new to Bikes (especially these) and I'm learning. I've modified and built many cars, but this will be my first modified bike. I've searched on this forum for an answer, and cannot find a definitive and clear answer for me as a newbie...

I have a '98 F3 with a Hindle slip-on silencer. The silencer was originally 20" long (stock pipe diameter). I cut 6 inches off of the can. I did this mostly 'cause I like the look, and it's a bit louder too! Now, I'm wondering if I need to re-jet the carb at all? Will the 6 inches less pipe make any difference at all? I just don't want to break anything, or sacrifice drivability.

Thanks in advance folks. Your help is appreciated.
Burnt Dragon (aka Mike)

 

Anyone?

 

You should be alright without a re-jet. You should still have enough backpressure with what's left of the muffler to keep your a/f in an acceptable range. Unless you've changed the air filter out for a high-flow one, you won't need rejet. It'll just make a good bike run worse, from what i've heard.

 

Thanks f3BikeR! I'm in Ontario, Canada so with all the snow and ice, I haven't been able to really stretch it's legs after the mod. However, a couple of Mondays ago, we did get a clear sunny day with a high of 1 degree celsius (lol) so I pulled the bike out for a carefull cruise around the block and it seemed to run fine. Mind you, I know the cold dense are has an effect on carb performance.

So the going to a high-flow intake filter will have a negative effect without jetting? Is there a real advantage then, to switching to high-flow filter and do a re-jet? Is the work worth the gains?

Thanks again in advance
Mike

 

Correct, it will have a negative effect without jetting because you'll be moving air into and out of the engine with the same amount of fuel in the ratio. This would cause you to run lean, rough, and hot.

Switching to a high-flow filter like K&N and BMC in addition to a jet kit will boost performance. A lot of people on the forums have done it, but sometimes it hasn't been a desirable modification.

Ultimately, more air + more fuel = more power so it would bring you performance in that manner, but it's a matter of proper tuning and careful work. Gains of 5hp or so seem realistic.

It's up to you. If it's worth the money, time, and work to do it then go for it. But some fellow hobbyists feel that it's better to leave a smooth running bike as it is.

 

Thanks for the tip f3BikeR!