Author Topic: 76 F model project- mono shock suspension(aka-Kingsnake)  (Read 139741 times)

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Offline dragracer

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Re: 76 F model project- mono shock suspension
« Reply #825 on: June 29, 2020, 10:21:56 PM »

The problem likely rests with 2 possible components.  The shift drum or i have a bad shift fork.
I don't think it's likely the drum or fork are at fault, Frank. I've never seen or heard of a bad drum, and you would have noticed a bent fork. The most common problem with 2nd gear is popping out of gear at WFO, due to worn dogs.
For the 1-2 shift, the air shifter needs to travel twice as far, which takes twice as long, as the other up-shifts. I would take a closer look there before splitting the cases. ;)

Its not jumping out of gear. The transmission was freshly under cut also. In the case of a shift drum, the pegs on the forks slide inside the tracks on the drum as it rotates. The  corners on the recess can become worn. Also, if a fork is bent, it cannot move the gear over far enough to engage on the upshot. I'm confident this is an internal problem,  especially after increasing the kill time between gears. Travel on the shift cylinder is more than adequate for the 1-2 shift as well.  Tearing this thing down is the very last thing I want to do but I've pretty much exhausted all other possibilities.  I will check the shift pawl engagement into the drum before I pull the engine off just to eliminate any chance a problem exists behind the cover.

Offline dragracer

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Re: 76 F model project- mono shock suspension
« Reply #826 on: March 22, 2021, 02:10:46 AM »
Have not posted in a while. I don't think i ever posted this time slip on the forum. I have only been on the bike once since this test session. I may eventually ride it in a Cup race in the super eliminator class. For now, my older brother will be in the seat  for the street ET class whenever we race again.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 F model project- mono shock suspension
« Reply #827 on: March 22, 2021, 08:36:06 AM »
Real nice Frank.  ;)

See you at Valdosta on my way back from St Thomas.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Old Scrambler

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Re: 76 F model project- mono shock suspension
« Reply #828 on: March 22, 2021, 10:10:04 AM »
 ;)...........you know how to 'build' & ride these beasts :) :) :)
Dennis in Wisconsin
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Offline dragracer

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Re: 76 F model project- mono shock suspension
« Reply #829 on: March 22, 2021, 11:41:34 AM »
;)...........you know how to 'build' & ride these beasts :) :) :)

I try my best Dennis. And I applaud you on your accomplishments on the salt. Not everyone can do what you do.

Offline dragracer

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #830 on: July 16, 2023, 05:35:57 AM »
Still sorting this thing out. L

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 F model project- mono shock suspension
« Reply #831 on: July 16, 2023, 11:35:11 AM »
;)...........you know how to 'build' & ride these beasts :) :) :)

I try my best Dennis. And I applaud you on your accomplishments on the salt. Not everyone can do what you do.

I'd bet you could Frank  ;) ;D
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline MRieck

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #832 on: July 16, 2023, 02:48:26 PM »
Still sorting this thing out. L
Did you rebuild that engine Frank?
Owner of the "Million Dollar CB"

Offline dragracer

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #833 on: July 16, 2023, 07:05:10 PM »
Still sorting this thing out. L
Did you rebuild that engine Frank?

That picture is of the mono shock bike. Not many passes on that build. I still have not done anything with my original F3 yet Mike. I need to freshen it up and put the new stainless steel valves in the head this time. My local machine guy isn't doing well healthwise. I've been trying to wait for him to get better so he can do the work. Unfortunately it seems he's not progressing well so i probably need to send it off elsewhere.  It'll  need a crank too.

Offline dragracer

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #834 on: October 26, 2024, 12:18:56 PM »
Made a test hit yesterday at Rockingham Dragway. Comparing this time slip with on of my best passes showed a a 4 hundredth  difference in the 60' times, 5 hundredths in the 1/8th mile and 8 hundredths in the 1/4 mile. I lost 1 mph as well.  I haven't been on the bike in a good while so I'm going to chalk some of the slower numbers up to lack of seat time. Another factor seems to be clutch slippage as i mentioned in a different thread. I'm going to concentrate on working more on the clutch set up as i move forward. The engine is still strong but my losses are through the drive train.

Offline dusterdude

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #835 on: October 27, 2024, 01:25:02 AM »
Keep digging frank

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Offline dragracer

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #836 on: November 07, 2024, 11:08:59 PM »
Well i started the process of installing the new lock up clutch. I had to do a bit of tweaking to get the air gap right so the arms can move properly. I'll probably begin with very light weight on thecarms and increase as necessary. I'm going to replace the clutch cable as well to see if it helps with lever release ease. I'd really like for this bike to have the same clutch feel as the F3 but I'm not certain I can exactly duplicate that set up. I've got a little time to finesse the clutch before the Manufacturers Cup event butvalso need to work on my other bikes. I'll keep pushing!!

Offline RAFster122s

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #837 on: November 08, 2024, 06:29:56 AM »
Interesting Frank, best on your juggling everything with holiday later this month you might have a bit of time to squeeze it in ...
David- back in the desert SW!

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Re: 76 F model project- mono shock suspension(aka-Kingsnake)
« Reply #838 on: November 09, 2024, 02:04:51 PM »
Got the lock up installed with a preliminary adjustment.  Time to put it on the ground to start it up for a final free play tweak.

Shop dog reminded me to read the instructions to be certain we didn't miss something important. 🤣