5 speed to 6 speed conversion?

[Shinchan_imp]

This is more of a placeholder question than anything, but I'm sure as time goes on and there are more totaled bikes/parts available, more engines being rebuilt, and as the book value of these bikes drops into the $3k-$4k range, this may start to be in the realm of possibility...

Has anyone been inside these engines to determine if the 6-speed trans could be a drop-in replacement for the stock 5-speed on the pre-'14 bikes? Did the actual tooling of the engine cases change between '13 and '14?

[venturer434_imp]

Shinchan, 5 Speed Gear Box to 6 Speed Gearbox was conceived with great ideas according to the CB1100 Drive Train Engineer - Yasuaki Mukai. You can read the article specific to the gear box in the following link.

http://world.honda.com/CB1100/engineer-talk/episode3/

[Lord Popgun]

Based on what was said it that link, and the fact that the crankcase part numbers are different, IMO the answer is no.

[kmoney_imp]

I'd say that it's basically impossible. Even if it were, buying all the 6-speed parts from Honda etc... it would be cheaper to buy an entire used 6-speed engine assembly and install it. It would also take probably 1/3 the time.

I don't know the costs for MC gears, but I remember when I worked as a transmission tech, people would ask us to rebuild their worn-out manual trans using OEM gear sets -- that idea usually died as soon as they heard the cost.

[Shinchan_imp]

I was thinking more of a "low-mileage, otherwise totaled bike" transmission, but I hear what you are saying.

Keep in mind that the newest bike I owned prior to the CB11 was a 1966, these are the things that vintage bike guys are always curious about as there tend to be plenty of donor bikes around

That being said, is the '14 engine a direct drop-in to the '13 and earlier frame?

I'd say that it's basically impossible. Even if it were, buying all the 6-speed parts from Honda etc... it would be cheaper to buy an entire used 6-speed engine assembly and install it. It would also take probably 1/3 the time.

I don't know the costs for MC gears, but I remember when I worked as a transmission tech, people would ask us to rebuild their worn-out manual trans using OEM gear sets -- that idea usually died as soon as they heard the cost.

[Randy B]

I was thinking more of a "low-mileage, otherwise totaled bike" transmission, but I hear what you are saying.

Keep in mind that the newest bike I owned prior to the CB11 was a 1966, these are the things that vintage bike guys are always curious about as there tend to be plenty of donor bikes around

That being said, is the '14 engine a direct drop-in to the '13 and earlier frame?

I'd say that it's basically impossible. Even if it were, buying all the 6-speed parts from Honda etc... it would be cheaper to buy an entire used 6-speed engine assembly and install it. It would also take probably 1/3 the time.

I don't know the costs for MC gears, but I remember when I worked as a transmission tech, people would ask us to rebuild their worn-out manual trans using OEM gear sets -- that idea usually died as soon as they heard the cost.

The frames are different part numbers, but they look the same in the pictures. The only way to know for sure would be to measure the mounting points.

The part numbers include a myriad of parts beyond just the frame so they could be identical, but I can't tell from the part numbers.

http://www.hondapartshouse.com/oemparts/...3267/frame

http://www.hondapartshouse.com/oemparts/...5a52/frame

[emptysea]

This is one of those threads that contain information I will never use, but I will follow it with great interest. (Until it's determined that it can't be done)

[Shinchan_imp]

You'll follow least for 40 or 50 years after the bikes are new until you get a definitive answer, just like with the CB450s

This is one of those threads that contain information I will never use, but I will follow it with great interest. (Until it's determined that it can't be done)