What would be some good mods for my 91 ultra? So far I got a k&n air filter and the rest of the bike is stock. I know I need a good set of pipes but will changing the head pipe make that much difference?I know I want to put a 21 on the front and lower the bike a bit..Some good engine mods is what iam really looking for..thanks in advance

 

Look, there are only three things to concentrate on:
1) Make it go.
2) Make it handle
3) Make it stop

Everything else is optional.

You've started to make it go. Remember to balance your mods. Since a motor is an air pump, free flow intake requires a freer flowing exhaust which requires re-jetting to rebalance the fuel needed.

To extend this further, replacing the factory cam will wake up your motor but only if you have done all of the above.

I'm not a fan of either 21" front wheels or lowering a bagger because it does not meet any of the three items I started with, but wtf, it's not my bike.

 

team depending on how many miles are your 91 , A good head job & some pistons will wake it up & a EV 27 cam for starters ,& also depends on your riding style

 

decent brakes - if you want to ride faster then you will need to stop faster

 

Team, you are mixing up two things here, one is wanting improved performance, the other is wanting to customise it. Now while I am not a traditionalist, I fail to see any merit in large narrow front wheels, which risk messing with both 2 and 3 in Beemer's list. You are also working with an old bike for which the parts that are available for recent models may not fit.

As for your questions, a change of head pipes isn't necessary, but decent mufflers will give a small improvement, as will a new ignition module. The reason for the latter is that the stock unit uses advance curves to keep EPA happy. Raised CR and ported heads all help, but IMHO don't try to mix and match yourself, call an established tuning shop for advice. They will be able to supply all you need and a set of components that will all work together.

 

Thanks guys, but like I said really looking for motor mobs,spark,fuel,etc

 

For making affordable, proven mods to your evo, this is some good reading for you below... Depending on your budget, you can build a stage 1, stage 2 or stage 3 level motor from your stock Evo.

http://www.nightrider.com/biketech/hdbuildstage2.htm

 

Step by step holmes, step by step.

 

The mufflers ( and exhaust pipes ) on your scooter are "flanged" if they haven't been upgraded. "Slip Fit" mufflers are not compatible. You'll need to use the head pipes of of a later model bike ... Hope this helps.

 

easily curable with the aid of a hack saw