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Honda's CBX1000 6 cylinder road bike has been the basis for a number of drag bikes including Denmark's Fin Asserbo, who built a Top Fuel version! In the UK there have been 2 CBX based Funny Bikes, and we will start off the 6 cylinder section with Andy Taylor's beast, campaigned between 1986-1998.
Over to you Andy:

The motor was a Honda CBX1000 taken to 1320cc, with a turbo and during the last season it was nitrous as well. Using a 100bhp shot of gas injected with methanol as an intercooler. We ran 35 lbs. of boost on the turbo running on C16 fuel.
We ran a 3 speed auto box, at the time it was the type where you couldn't back it off in 1st or 2nd without breaking it due to the shift system and we often bent selector shafts and forks due to minor misfires!

We dyno'd the bike on 20 psi of boost and no gas and it made 300bhp with lots of tyre smoke, the dyno couldn't hold the bikes' power surge when boost came up coinciding with the motor coming on cam at about 9,000 rpm. We had developed our own cams and rev'd the motor to 15,000 rpm. We tried to nurse it past that point on higher boost but as soon as you hit full throttle either it went up in tyre smoke or the dyno would shut down as it had peaked past it's 500bhp limit. I think we were making around 450bhp to be honest, but the surge was too much for the dyno. We were seeing around 200bhp at 8,000 and about 5psi of boost and that went to over 400bhp at 9,000 and that's a huge surge for the dyno to hold. On the track it didn't matter as we would launch the bike at around 10,000 anyway.

We used a heavily modified head with dramatically more flow than standard to go with the larger cc and oversize valves. Our con rods were aircraft spec alloy to our own design and would not fit in a CBX motor any smaller than 1320cc due to size, but were still less than half the weight of the standard ones. The clutch was spring steel banded and used a centrifugal locker and very heavy springs and was heavy to use even with the hydraulic conversion.
We ran a specially made Scintilla magneto ignition with parts specially made for us to allow it to run at the revs we wanted. Back then the electronic units didn't have the power at those revs. The bike was built by myself with the help of my crew and as I'm 6'6" tall, I built the chassis to fit me which meant that no-one else got to ride it!

We ran regular mid 8 second quarters. Then after stepping up the power with the addition of the nitrous, we ran 4.91 @149mph at the eight mile with the bike refusing to go into top gear.
We replace the selector shaft and forks and it did the same again at 4.93 at the eight, before the gearbox let go in a major way as soon as I pushed the button for top gear. It shattered the drive dogs off, split a chunk out of the gear and threw it at the back of the crank hitting a con rod. Trapped between the barrel and rod it broke the liner. The sudden loss of drive let the motor momentarily over rev and it tangled half a dozen valves.
This pretty comprehensively destroyed the motor at half track and the bike rolled through the top end in 8.6 seconds at about 90mph coasting.
I believe that it would have run around 7.70 on the quarter if it had all stayed together, and the top end surge would have seen us up to about 180mph.

The bike weighed about the same as a stock Honda CBX and had 4 times the power. Only being completely out of cash prevented any further development but by then I had been racing a long time and it was time to move on.

Even after all this time I still occasionally get people come up to me as they remember the bike, I only wish I still had it (sometimes) at least to bring it out from time to time as a piece of nostalgia, I wonder how many of the old bikes are lurking in a garage somewhere?

Note the magneto drive and hydraulic clutch conversion in this photo.