Any ideas on how much drop for hardtail...

[jbgore]

I plan on running an 18" rear wheel, 21" front wheel, forks lowered about 2" ( I just like the way the lowered forks look), and I'd like the lower frame rails to sit more or less parallel with the ground. I'm planning on high pipes, so exhaust clearance is not a big concern, but I want enough clearance to ride without scraping.
I'm planning on a David Bird hardtail, but I'm not sure about what drop would be appropriate. It's a little too expensive for trial and error on this choice, if there's any way to avoid it.
Any recommedations on the drop I'll need based on the info I've given?
Thanks for the help.

 

[david bird]

Here are some examples for the rear, with the frame rails level.

250 x 18 tire with 0 drop the frame rails should be 4.5 off the ground

275 x 18 tire with 0 drop the frame rails should be 4.625 off the ground

300 x 18 tire with 0 drop the frame rails should be 4.875 off the ground

Each inch of drop in the hardtail will take off 1 inch on the above #s

 

[jamesgs4]

Also figure in droop, and that depends on how much you eat and drink.

 

[jbgore]

David,

Thanks so much for taking the time to respond. I'll most likely run an Avon SM 4.00x18 rear. I've also considered the Avon SM 5.00x16 rear. Any thoughts on best drop for either of those tire sizes? Dennis Kirk lists inflated diameters at 26.7 and 26.4, respectively.
Thanks again.

 

[david bird]

Jb
I figure all this in auto cad, and with the 4.00 x 18 and the diameter that you give I come up with 4.24 from the bottom of the rails to the ground using a 2” drop. The other one will be .3 less. All this may vary a little depending on who is setting it up and taking the measurements. I hope this helps. dave

 

[jbgore]

Thanks again Dave. I'll be ordering my hardtail soon. My son is making as much progress as school and work allows on cleaning up his frame and getting it ready to weld on the loop tail you sent him on Christmas eve. Since he says I can't "copy" him, I suppose I'll go with a straight tail version.
I appreciate your willingness to jump in and answer questins on your product, as I'm sure the other forum members do, as well. If I could get my son to pay as much attention to college as he has to your MIG DVD, he'd be making straight A's for sure!
Have a great day