special tools

These beam type wrenches are notoriously inaccurate, especially on smaller fasteners.

I have a 0-150ft/lb Craftsman beam torque wrench that's very accurate in the middle of the range as tested with a friend's snap-on. Where the beam wrenches lose their accuracy is at the ends of their range so you want to use them only in the middle 50% of their range.

That being said, I've tested my Craftsman microtorq clicker wrenches and they have both shown accuracy within 3% even at the extremes of their range. As stated before, if you leave their plastic locking rings alone, you'll never have a problem with them. At only $44 each, nothing else comes close to them for bang for the buck. If you have money to burn, get a couple of Snap-on's.

I hear you (sort of) but Id rather spend 100+ on a good wrench than 300 on a clutch hub. Just curious, how were you testing your torque wrench to come up with that number?

A buddy of mine manages a jet engine facility for General Electric and I used his calibrated Snap-on wrenches for comparison. My off the shelf Craftsman microtork wrenches were almost spot on. Even my 10 year old 25-250 inch/pound wrench.

What the hell are you doing to wreck a clutch hub? I never used a torque wrench until about 15 years ago. I still don't use one on clutch baskets and have never had a clutch failure. I only bought a 3/8" 0 to 25 when I bought a thumper in 2000. I've been working on bike and cars since 1972. Having said that, I'm going to Sears and buy another. I've heard that most torque wrenches lose acurracy at the top and bottom of their ranges.

Yep, you don't want to use any torque wrench at he extremes of it's range. This is why every garage needs 3 torque wrenches to cover every nut/bolt on a bike. That being said, the small 25-250 inch/pound wrench is what I use 90% of the time.

If you're not using a torque wrench on your clutch hubs then a failure is inevitable. It can happen to the best strong arm torquers.

I guess it depends how deep you plan to go, and what type bikes you'll be working on. I definitely agree that a good torque wrench should be your first purchase. As far as real "specialty" tools, check your service manual. It should list the factory tools specific for servicing our bike. Read the manual and see where and how they are used. If the tool is needed for a job you plan to tackle, find out the tool cost vs. having the job done. Make your decision based on how often you'll be doing this type work.
Here's some generic tools that may not be in your average tool box, but I've found to be very useful.

T-handle - This will speed your work. I use the type with a 3/8 socket drive and slide handle. IMO, the T-handle sets with sockets take up to much space. You typically use only 1 or 2 sizes regularly. The slide handle allows you to apply more torque when you need it.

Digital caliper - You don't need a top of the line professional machinist grade. It just needs to give consistent readings. I've found valve shim markings way off, or even unreadable. I always measure a shim before installing and it's saved me countless hours.

KD tools piston ring compressor - It's a split band design that can be used for bottom insert. If you're only doing single cylinder bikes occasionally, you an get by with the fingernail method. The 3 piece oil rings on 4 strokes can be a challenge. I broke down and bought one for a multi-cylinder project and it's been worth every penny.

Valve spring compressor - obviously a 4 stoke only tool

Flywheel puller - Cam chain or crank seals, you're going to need it eventually

Hydraulic press - I bought a 20-ton press for an automotive project. I've found I use it way more than I thought I would on bikes. Need to replace steering stem bearings at 1A.M.?...no problem! You can get a press from Harbor Freight for just over $100 if you catch them on sale and with the 20% off coupon they have in every ad.

Impact Driver - both the hand type you strike with a hammer and pneumatic (or cordless if you don't have air). Just a word of caution on impact drivers. Only use them as a last resort. I try breaker bars, pipe extensions, penetrating oil (I like PB Blaster), heat and any thing else before getting out the impact driver. When you pull that trigger, something is going to give. It may not be what you intended. Which brings me to...

EZ outs, tap and die set and a tread repair kit (helicoil or similar) - Sooner or later, things are not going to go right. It usually happens the night before a race. You need to be prepared to remove, repair and replace any broken fastener before you start. This really should be at the top of the list. You hope to never use them, but you'll be so glad you have it when you do.

Not a strong arm guy here, just some patience and common sense. The tension of the springs will keep clutch bolts from backing out, they kinda work like lock washers. I usually bottom them out and then no more than a quarter turn. The only probs I've ever had with a clutch was just wearing them out. I don't really hammer clutches when I ride either.
As far as electric impacts I only use them to remove fasteners, much faster on a bigger job like splitting cases.