I have a bit of dragbike experience from back in the day, so here's my 2 cents.
What 754 said works, it's what we all did.
'Strapping' the front end down is basically taking a tie strap and cinching the fork brace to the tree, compressing the forks to where they don't allow 'rebound' extension on the launch. The idea is to transfer weight to the rear tire when it needs it most. I've seen it done in the past with good results, especially on high torque bikes. Things like air fork caps run at decent pressure will stiffen the forks, and the heavy oil in the forks don't allow them to extend as quickly.
I machined tubing 2" long to use under the dampening rod (I think?) that made the forks OAL shorter. I cut the springs down some as well. It was pretty common back in the day; it worked, my forks are shorter, the bike got lower, and I had no issues.
Struts as a replacement for rear shocks will allow you to drop the tail dramatically, aids in weight transfer, and they are much lighter. The tendency of a rear suspension is to 'squat' when power is applied to the rear wheel. Look at a good bracket car, the tail will raise when they launch. Energy isn't being wasted. Until you get into VERY high horsepower, weight transfer issues are primarily limited to the launch and first 60 feet.
When using struts, there is no swing arm movement so your chain length is a constant, of course allow for adjustment. The stock type adjuster section worked with a lengthened swing arm, at least I didn't have issues in several applications.
Modern motorcycle drag tires have a much more squared off sidewall than those of the past, you get as much foot print with a 7" tire now as you did with the old 8-1/2". I had no clearance issues running the 7" tire but it was tight. I used an ('ultra duty') double row drive bearing and F-2 solid output shaft, they're machined to take the wider bearing. Don't remember if those fit a 'K' case, but you can get a beefy bearing for it.
Removing weight gives a better horsepower to weight ratio, allowing quicker acceleration. Removing things like the electric starter and running a smaller, lighter battery are simple.
Remove as much rotating mass out as you can. Using light wheels, drilled rotors, eliminate alternator (or use a lightened one) these are where your largest gains in acceleration come from.
A GOOD 520 chain will withstand plenty of abuse. As far as the length, just bite the bullet $$ and get what you need. Of course be careful when installing the master link clip, and if you dab some silicone sealer behind it, it will not come off. At least I've never seen it happen when done this way.
I've made offset sprockets by machining an old one as a spacer, then welding them together. This wasn't as easy as it sounds. I can tell you they're harder than the hubs of hell, and carbide inserts don't look brand new when you're done. And you're very limited in offset due to shiftdrum linkage interference.
I'm not sold anymore on such low ground clearance - even though MY bike only had 2" of it. Many of the old school funny bikes had plenty of it. In my opinion, there are better methods of aerodynamic control. Bonneville has shown that 15 HP can produce 100 MPH. However, the stance is #$%*in and people DO notice that.
Air shifters are wonderful. You never miss a shift and it happens VERY quickly. I still have one on my street bike, it doesn't interfere with normal foot shifting. At the strip it's no big deal to refill the air bottle, you can make a couple runs between fills. I believe NHRA sanctioned series require a certified pressure vessel, so check that out before a making a purchase.
Wheelie bars can be great, they can give you confidence in your launches. If you like the looks of them, then get a set. Do you really need them? The very good, really fast outlaw pro street guys don't use them, but myself I prefer them.
