Topic: 76 F model project- mono shock suspension(aka-Kingsnake)

[dragracer]

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.

[dragracer]

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.

[Jerry Rxman Griffin aka MuthaF'er]

Real nice Frank. 

See you at Valdosta on my way back from St Thomas.

[Old Scrambler]

 ...........you know how to 'build' & ride these beasts

[dragracer]

...........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.

[dragracer]

Still sorting this thing out. L

[Jerry Rxman Griffin aka MuthaF'er]

...........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 

[MRieck]

Still sorting this thing out. L

Did you rebuild that engine Frank?

[dragracer]

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.

[dragracer]

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.

[dusterdude]

Keep digging frank

Sent from my SM-S711U using Tapatalk

[dragracer]

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!!

[RAFster122s]

Interesting Frank, best on your juggling everything with holiday later this month you might have a bit of time to squeeze it in ...

[dragracer]

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. 🤣

[Don R]

 I miss having a shop dog, my old St. Bernard would play tug all day so I'd tie his tug strap to a car once in a while and let him tow them in and out of the shop. When I was working under a car he would crawl under too.

[MRieck]

I'd start off with no weight on the arms Frank. When it locks up in 1st it takes a lot of pressure to get it into second secondary to the how far the gear has to travel. Air shifting will more than likely handle the change up but it is real hard on the fork. I ran into problems using an MRE unit on my FJ.

[dragracer]

I'd start off with no weight on the arms Frank. When it locks up in 1st it takes a lot of pressure to get it into second secondary to the how far the gear has to travel. Air shifting will more than likely handle the change up but it is real hard on the fork. I ran into problems using an MRE unit on my FJ.

Mike, good recommendation. My biggest dilemma is i won't have time to test the new setup before the actual race event. Round 1 of Qualifying begins in Friday evening. And we may get 2 on Saturday.  I need to make each one count because i intend to put a nitrous tune up in the bike to qualify on spray. The extra horsepower will likely cause clutch slippage as the nitrous ramps up towards my final percent  if I'm to light on the lockup arms.  In the other hand, i have to balance what will happen to my 60' times and your reminder of the bike having difficulties shifting under a continuous load from the centrifugal clamping  force of the lockup arms. If i had the ability to test prior to the event I'd definitely begin with no weight and add as necessary.  I'm probably going to keep a minimum amount of weight on the arms for Friday testing and see what happens.  I'll have time overnight to remove the weight prior to the 2nd round of Qualifying if the bike exhibits shifting problems or if my 60' times go to crap. Nevertheless,  i have a 7 hour ride down to Valdosta to make a final decision. I'll keep you all posted.

[Don R]

 Good luck, our fingers are crossed for you.