Short hubs

Tim Lewis · Posted: Tue Oct 23, 2001 7:22 am Post subject: Short hubs

Hey gang,

I'm looking to put some short hubs on the rear of my kart. I just got some 65mm ones and realized they are the same as what I already have. They looked shorter just due to the optical illusion of how they were machined. So here's the question.

1. What are the shortest rear hubs you can find?

2. How much of a difference in hub length is meaningful? Can you feel a 10mm difference, or does it take 50mm to feel?

So there you go, let me have it!

Tim Lewis

Tim Lewis · Posted: Tue Oct 23, 2001 4:24 pm Post subject: Short hubs

If anyone is interested...

The 65mm long Trackmagic rear hubs that I bought got in a fight with a lathe and they are now 50mm long Trackmagic hubs. When I get a chance to run them, I'll give a report.

Tim Lewis

Jimmy Moore · Joined: 26 Jul 2001 Posts: 664

Tell us where they crack.

Steve Rickman · Posted: Tue Oct 23, 2001 10:47 pm Post subject: Short hubs

Tim,
That is about as short as they get. As far as what makes a difference, 10mm will make a small yet somewhat significant difference.

Steve Rickman www.genesisracingproducts.com

Tim Lewis · Posted: Wed Oct 24, 2001 6:56 am Post subject: Short hubs

I'm guessing it will help crack the 45's at Adam's. I'd love to send them to PA for a try, but you've probably already had to put your kart up 'till April!

Tim Lewis · Posted: Mon Nov 19, 2001 8:28 am Post subject: Short hubs

OK, I finally got a chance to run these things yesterday. Pretty good results. I've ran a bunch of laps at this track (Adams) over a 3 year period.

I went on the track with my base set-up and ran on old tires to get me up to speed. Then I bolted on a set of stickers and ran a session. I ran a 46.03(my fastest ever vs. 46.07 previous best) with this arrangement. I put on short hubs with the same overall rear width. 3rd timed lap was a 45.93 once I saw a 45 on my dash I went into qualifying mode and ran a 45.58.

Was this change worth a solid 1/2 second, no, I wish it was. I haven't been on good tires for a while, and that was a major contributor. I would say my 46.03 and 45.93 were driving about the same level of intensity. The fast time was definitely 'hanging it out'.

Overall, it seemed to reduce hop a small amount and allow me to hit my apex's a little better. It also seemed that the recovery once the kart got loose improved a little. None were big changes, but noticeable.

To answer Jimmy's question. The cracks start at the base of where the cap head bolt seats. The MkII model will have a stepped inner bore instead of just shortening.

So there you have it.

Tim Lewis