Redline

[TADracer]

Dan makes an excellent point. Your optimum shift point is the exact RPM where your motor is making the most power and torque, not the factory redline on the tach. Pass that point and you are just wasting motion and maybe even hurting your overall acceleration because your motor is no longer on the sweet spot.

The redline is nothing more than a mark that the factory does not want the rider to exceed, probably for their liability purposes or something.

If the expense of a dyno run, or six, is not in your budget then take it to a Wednesday night test & tune at the local dragstrip. Ten bucks and you will have some fun finding the shift points that just feel right and give you the best times.

[Dan Hodges]

Valve Springs

You can buy valve springs for the XS from either Web Cams, MegaCycle cams or Kibble-White who actually makes the springs for all of them and you can find all three on the web. A word of caution about stiffer after market springs. After market cams are of the hard weld type and the lobe surfaces are very durable as opposed to the stock cams which sometimes can be prone to premature lobe wear. A fresh (new) set of OEM springs shimmed .040 will work out nicely with the stock cams. A stock Eleven with 20,000 miles or more needs fresh springs if you are going to spin it to 8,000 plus rpm. Springs lose their tension primarily because of heat and even though you can't tell it by the seat of your pant's, the valves will begin to lose their ability to seal properly with the seat at high rpm once they lose 20% or more of their seat pressure and the open pressure is even more important. I have a spring tester that I use to measure valve spring tension/pressure however unless you have the ability to test your's, it's best to simply buy a new set of springs, shim them .040 and be done with it. Yes I know that stock valve springs will last forever however that's not what we are talking about.

[81xsproject]

I have seen the springs for sale at KW, but have not seen ANY vendor of high end valves. I would love to know if you do know of one, Dan.

PS how's the 1311 coming?

[Dan Hodges]

Kibblewhite Precision Machining Inc.

Originally posted by 81xsproject
I have seen the springs for sale at KW, but have not seen ANY vendor of high end valves. I would love to know if you do know of one, Dan.

PS how's the 1311 coming?

Kibblewhite (KPMI) manufactures valves in a multitude of sizes and materials and will make custom sizes and orders (XS11) from blank stocks. They also make custom guides, seats, custom shim under bucket tappets and titanium retainers. They don't stock OEM type XS valves but will custom make to order anything you want when it comes to valve train parts. All you have to do is send them a valve and they will duplicate it in any configeration you want. Their number is 650.359.4704. I believe Manley Performance also makes custom order valves for motorcycles and I have used their car stuff but have not seen any of their motorcycle stuff. Basically, you can get anything you want if you want to pay for it. The upper crankcase machine work has yet to be completed on the 1311 project. The upper case has to be relieved (enlarged) to accomodate the larger diameter sleeves. I bought another motor to do this project because I didn't want to go back into the 1179 as I just went through it in the winter of 06-07 and the lower end of the motor I bought required some major work to get it right. Summer time is a busy time for me but during the winter I will have some time to finish it.