KX Riders

Maintenance & Technical => KX500 Steel Frame Conversion (SFC) => Topic started by: umberto on August 01, 2015, 10:58:34 AM

Title: KX 500 Engine Weight versus KX 250 Engine Weight
Post by: umberto on August 01, 2015, 10:58:34 AM
I was reading some stuff today, and I think I am going to try working on the suspension myself.  I was going to order gold valves and springs for my forks and shocks, but I'm not sure how much the K5 motor added to the overall weight.  Has anyone ever weighed the two and compared?  I tried the search, but flywheel weight is a pretty prevalent term.
Title: Re: KX 500 Engine Weight versus KX 250 Engine Weight
Post by: zz3gmc on August 01, 2015, 11:13:18 AM
My bike was my old 250 race bike so I left the suspension alone. Im using 03 forks with the standard springs .42s and a 5.4 shock spring. I had them revalved when I bought the bike new(03 forks were revalved later). I noticed that the suspension actually works better as a 500. Im on the gas alot more on a 250 and it puts more load on the rear. On the 500 im always a gear or 2 higher and the suspension is more relaxed therefore it doesnt "pack" or deflect near as much as when it was a 250. I ride tight technical woods and not much open stuff.
Title: Re: KX 500 Engine Weight versus KX 250 Engine Weight
Post by: sandblaster on August 01, 2015, 11:22:54 AM
89-04 kx500
62 LB WITH OIL AND SPARK PLUG, NO CARBURETOR, no kick lever

95 kx250
55LB WITH SPARK PLUG, KICK LEVER, REED, AND BOOT, NO CARB. NO OIL, SHIFT LEVER

Roughly 10lb.
Title: Re: KX 500 Engine Weight versus KX 250 Engine Weight
Post by: umberto on August 01, 2015, 11:28:20 AM
That's not a huge difference between the two, so I think I'll stick with zz3gmc's plan and go with springs that fit my weight category and not really worry about the added 10lbs.  It sounds like we ride pretty similar terrain.  It's not like I race anymore, I just didn't want to mess the suspension up right from the get go. 

Thank you for the help gentlemen!!
Title: Re: KX 500 Engine Weight versus KX 250 Engine Weight
Post by: zz3gmc on August 01, 2015, 12:20:28 PM
The shock spring on the 04 250 is a 5.2 standard. I went up one size to the 5.4