Wilsons Sandbox

Posted: **Tue Jun 20, 2000 4:22 pm**

In a message dated 06/20/2000 4:18:17 PM Eastern Daylight Time, rob@... writes:

> Does anyone know how to calculate/determine the compression ratio of any > given four stroke cylinder? > > Rob >

Can't find my reference book right now _Design and Tuning of Competition Engines_ but I think you can calculate it this way: Take the amount of fluid displaced by the piston when going from BDC to TDC and divide it by the amount of fluid left. Or it could be the total amount of fluid held (the amt. displaced + amt. left) in the cylinder divided by the amount left. I think one way is the theoretical CR and the other is the mechanical CR. I'm sure somebody on this list can clarify. If not, I'll find my little red book of formula and post later. Knot - who knocks before detonation and sometime preignites

Posted: **Wed Jun 21, 2000 10:24 am**

At 1:35 AM -0400 6/21/2000, JSherlockHolmes@... wrote:

>Thanks for the input on tires. Got a couple more questions. What are the >opinions of Cheng Shin tires? Used to use them on our dirt bikes, back a few >years. Never had experience with their DP tires. Has anyone heard of Maxxis >tires? They have an interesting looking DP tire, but I have never heard of >them. > >For the devout Kenda users, I located a supplier that is substantially less >expensive for Kenda's than Dennis Kirk. It is www.bobscycle.com The >5.10-17 is about $20.00 less, and the 3.00-21 is about $7.00 less. Just >thought I'd share. > >The correct tire size is 5.10-17 for the rear, and 3.00-21 for the front, >isn't it? Or 90/90-21 for the front and 130/80-17 for the rear? Is it safe >and functional to go to a 3.25-21 tire on the front, get a little bigger >footprint on the front?

Yes, the Maxxis tire I was checking out had what appeared to be a versatile tread pattern, but I never got around to buying a set. I had Chengs and found them to be way scary on wet pavement vs. the Kendas. Yes, the 5.10 / 3.00 combo is correct. I currently have a 3.25 on the front of the A2. I mounted it about 500 miles ago as I was curious about this size. I 'm not sure I really notice a difference other than I paid an extra $5. The 3.25 might cup less because of the slightly larger contact patch. But then, it might cup more; we'll let the engineers debate that. I'll let you know what I observe in a few thousand miles. Mark B2 A2

Wilsons Sandbox

[dsn_klr650] nklr: tires ii

[dsn_klr650] nklr under pressure

[dsn_klr650] nklr: tires ii