Author Topic: CB750 AHRMA Sportsman 750 Racer  (Read 43655 times)

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Offline gschuld

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #925 on: February 27, 2019, 11:43:22 am »
Great job Matt.  I’m glad last weeks scare and thrash to correct the problem ended in a good result.

George

Offline Tintop

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #926 on: February 27, 2019, 12:42:19 pm »
Great result, thanks for the race report.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
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Offline Rocketman

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #927 on: February 27, 2019, 05:43:03 pm »
Well done Matt.  A great start to the season!

Offline bear

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #928 on: February 28, 2019, 05:34:37 pm »
Well done Matt, it's nice to start the season with a win.

Just out of curiosity,  what's your opinion on the new clutch.
The older I get the faster I was.

Offline dragracer

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #929 on: February 28, 2019, 09:18:13 pm »
Great way to end what initially seemed to be a heartbreaking start to the season. Thanks for the detailed report. I wish I could have been there to watch you take the win but I forgot about my work conference in Hilton Head that weekend. Hopefully I can hang out next time you're in my neck of the woods.. Looking forward to the next race report. 

Offline turboguzzi

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #930 on: February 28, 2019, 11:17:10 pm »
Hei matt, congrats form me too, specially after what you been through before leaving. You didnt mention much how all your winter work performed... or what didnt :) did it reflect on lap times?

Offline Sam Green Racing

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #931 on: March 01, 2019, 03:56:51 am »
Congratulations Matt and what a great report, well done and good luck for your next outing at NOLA.

Sam. ;)
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Offline bwaller

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #932 on: March 01, 2019, 04:34:34 am »
Well done Matt. I especially enjoyed the perspective of your better half along the way.  ;D I know Deb always helped me keep it on the rails, so it's good to have someone who cares about us watching our backs!

Was it the clutch that was grinding when you first started it? And if the trash settled out of somewhere over winter, that is odd. In hindsight could you have removed from underneath with just the pan removed?

By your report you probably had dry track only for your first weekend with the 3CR's. Any tire feedback? I'm trying to draw out what I can from these tires but there doesn't seem to be anyone at this point, who has previously used the 2CR's in the wet to give an opinion on the new ones in the wet.

That and the fact that they are just bloody tough finding anyone with inventory.  ::)

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - Roebling Road
« Reply #933 on: March 01, 2019, 05:50:44 am »
Thanks to everyone for the attaboys!! It sure is awesome to have such a great community of riders and racers following along.

Well done Matt, it's nice to start the season with a win.

Just out of curiosity,  what's your opinion on the new clutch.

I went back to the old clutch under the assumption that it ran with the old clutch, I changed the clutch, so it must be the new clutch. I wish that was the case as it ended up be some crap in the trans. That did, however allow me to find the gears that were taking their last breath so I guess its a good thing, especially now that its in the rear view mirror.

Great way to end what initially seemed to be a heartbreaking start to the season. Thanks for the detailed report. I wish I could have been there to watch you take the win but I forgot about my work conference in Hilton Head that weekend. Hopefully I can hang out next time you're in my neck of the woods.. Looking forward to the next race report. 

It would have been a blast to have a SOHC brother down there for moral support. Fortunately, the most off track excitement I had with the bike was missing a piece of safety wire on my sprocket nut and a slightly loose gear change linkage bolt. I really enjoy not wrenching at the track. I would really like to make a habit of it.

Hei matt, congrats form me too, specially after what you been through before leaving. You didnt mention much how all your winter work performed... or what didnt :) did it reflect on lap times?

No real winter work to speak of. I put her up for the winter after draining the fuel and getting the battery on the tender, and that was it. Stood to reason that if it ran at Barber, it should run now. Guess not. I have learned a valuable lesson here on making sure it starts and runs well before go time. I will try the new 4 plate clutch again for the Road America round (next race after NOLA) and see what happens. I would like to ride the bike a bit to break the clutch in a bit and get the grabbiness reduced and I can only do that when the weather breaks.

Additional changes for the year are a new seat, adding a front fender and the already done AP racing front caliper. Performance and engine wise, Im going to go through this season with what I have.

Well done Matt. I especially enjoyed the perspective of your better half along the way.  ;D I know Deb always helped me keep it on the rails, so it's good to have someone who cares about us watching our backs!

Was it the clutch that was grinding when you first started it? And if the trash settled out of somewhere over winter, that is odd. In hindsight could you have removed from underneath with just the pan removed?

By your report you probably had dry track only for your first weekend with the 3CR's. Any tire feedback? I'm trying to draw out what I can from these tires but there doesn't seem to be anyone at this point, who has previously used the 2CR's in the wet to give an opinion on the new ones in the wet.

That and the fact that they are just bloody tough finding anyone with inventory.  ::)

It was great having Ashley along for the ride. Im happy to report she is a convert and quite disappointed she wont be coming to the NOLA round, but will be with me at RA, Gingerman and Barber.

I determined it was the lack of engagement from the gear dogs that caused the horrible grinding sound, but there was some rubbing on the inner pressure plate on the new clutch as I added an additional steel to get the pack thickness to where I understood it should be. Ill play with the new clutch when the weather breaks.

We ended up finding 3 pieces of the "trash" which I believe to be ceramic media, the last of which fell into a bearing packet where the trans roller bearings live as we were putting the case halves back together. Good thing it kept us from doing our job and we found it or it would still be in there. The other two were in the oil pan when we pulled it.

I ran the Avon's this weekend as they were new before Barber. My plan is to run the Avon's at NOLA next weekend, switch to the 3 CR's for RA and Gingerman, go back to the Avons to wear them out at Tally (VERY abrasive track, where even worn out tires stick like slicks) then back to the CR's for Barber. If I like what I feel from the CR's, they will be my new tire and will run a fresh set each season, depending on the number of races I run. With the patchy availability of the 3 CR's in the US so far, there have not been any AHRMA reports that I have read but Im sure some from NOLA will come out.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #934 on: March 12, 2019, 08:46:27 am »
Load em up! Load em up!

Well, NOLA has come and gone and it was a great weekend overall, with the weather holding off and the racing being the best I have been a part of.

The weekend started on Monday of last week driving 60 miles in Michigan winter to get my brothers bike from his house since he didnt have access to a trailer. Tuesday was a race to get everything packed up after work but before the really frigid cold set in. It was running around 15F or so during the nights so I wanted to get done as soon as possible.

Loaded up:


The drive to NOLA was uneventful which is my preference. We stopped in Tuscaloosa for the evening on Wednesday and finished the drive Thursday morning, getting to the track at about 1pm.

The long bridge over the bay in New Orleans:


We dropped the trailer and headed into town to find Bourbon Street. I had never been so worth checking out. I did find that the stores and scene got pretty repetitive quickly though, so a few hours was all I needed to get my fill.

Classic Mardi Gras apparel:


Shrimp Po Boy (looks lackluster but was amazing, along with a Pecan Praline Root Beer)


Back to base camp and it was time to settle in. Being on the edge of a time zone during winter and the night comes awfully fast so there wasnt a whole lot to see as we wrapped up our track walk. It was a good thing we did it though as the surface was very bumpy from the cars, Indy cars and Super Semis that were raced there. Definitely the bumpiest surface I had ever ridden on.

Friday came with some good weather but we pavement. Its pretty humid already but the sun managed to burn most of the moisture off the tarmac early. I got tech inspected and it was time to get after it. Practice round 1 for me on a new track is always pretty slow and steady, and for a bumpy track like NOLA, learning not only where to go, but where not to go! The best race line was in some instances very rough so modifications needed to be made and riding style adapted. One corner was rough enough that I had to weight the pegs and get my butt off the seat to not upset the bike! Lap times for practice 1 were in the 2:32 range, well outside the 2:10-2:15 needed to be competitive.

Round 2 was a success and I was able to get down to a best of 2:23, but still needed more. Practice 3 and 4 say bests of 2 2:22 and 2:18 respectively, still improving but not enough to make me really happy.

Friday night was the awards banquet for the 2018 champions which was really cool. I got to see my uncle hand off his #1 plate to my cousin Nick. A very special father son moment I hope I can share with my son Jackson one day.

The food was unreal, being treated to a seafood corn chowder and sausage pasta, as well as a short rib jambalaya which was some of the best food I have ever had. The jambalaya was by no means pretty food, but the taste more than made up for it. With my belly full of great food and beer, it was time to sleep.

Saturday came and with another clean bill of health from tech, the bike was ready for two rounds of practice and racing in the afternoon. We were race 12 so plenty of time to kill before go time.

Times in practice were consistent and I tried following my uncle Jeff around to get a feel for how fast I could really go at this track. Watching him helped some but I still felt like I was going to have to work my a$$ off to get a good result.

I will get my videos up soon, which are far more exciting than those at Roebling. Saturday's race had Nick on the pole, me to his right, and my uncle Jeff to my right, all lined up. The fourth guy in our class was lined up right behind us and it would be a drag race to turn 1. I got my usual average start and I was off, right in behind my uncle in 3rd place. Nick is so fu*king fast that at this point, beating Jeff was the real practical goal for the weekend. I was hot on him through the first lap or two, then comes the other guy in our class, getting a run on me and making the pass. Now its 3 bikes nose to tail, with me taking up the rear, Kendall Cranston just having passed me, and Jeff up front. The battled and I waited for my chance. I could see where they were slower and I was faster and I planned my move. I will have to watch the video to see where and what lap but I was able to get my pass in cleanly and started working on my uncle. Jeff is a 4 time champion of the class and knows how to ride very well so the competition was very stiff. Again I could see where he was slow and I was faster and was able to show a wheel a couple times but couldn't convert. I nearly packed him in the a$$ a couple times which I should have converted into a pass but it never quite worked out. I rode my heart out and while I was able to keep him close, I never did make the pass, with me finishing just over 4 tenths behind him, and Kendall just over 1.5 seconds behind me. I got my wood for the day and was ready to get after it tomorrow, hoping for a good start and the ability to make some key moves. I did however get my best lap down to a 2:13.147, beating my uncle's best lap time of 2:13.224!! Ill count that as a personal victory any day!

Your main main with his new wood:


In the hunt:




Pure sex even from underneath:


My brother and I before action on Saturday. Im awfully proud of him! If it wasnt for some oil issues, he would have gotten his first wood this weekend. We will get him sorted and back in the hunt for sure


Sunday morning started just like Saturday with tech and practice in the morning. Typically AHRMA does one practice in the AM on Sunday then goes to racing before lunch just to get things moving so people can start driving home. Well that didnt happen and after a computer crash, the grids were all screwed up and ended up being hand written so there were 2 practice sessions anyway to get it all sorted. I skipped practice and figured I would save energy, fuel and tires for race time. I did do a quick scrub lap just to check everything out after a very hard race on Saturday and all was good.

Now all four of us were lined up in one row, so it was another drag race to T1. I got an even worse start than Saturday and took T1 in 4th place, but I was hot on Kendall Cranston. Jeff hit the after burner and went hunting for his son Nick and ended up turning lap times that were all better than his best on Saturday. I at least had to duke it out with Kendall and get my 3rd place, both for season points and self respect. He was fast but I knew I was faster. My first pass on him was a deep braking move and didnt stick so I spent the next 2 laps following him, again to see where he was fast and slow. The last couple of turns before the front straight can be taken in a few ways which is where I figured I would be able to set up my pass for 3rd. I saw the crossed flags (half way) and followed him for the rest of the lap, setting up to get a drive out of the last few turns. I have motor on everyone in the class, and even despite me and my bike being heavier, I can reel most guys in on a long (3200 feet here) straight. Well I got my drive and came out right behind him. You have to hug the wall as the rest of the straight is pretty rough and wallowy, I had just enough room to split him and the wall right after the finish line to safely make the pass and take T1 ahead of him. I could hear his bike the whole rest of the race and knew he was waiting for me to screw up, but I never made enough of a mistake to let the happen, despite a couple trips out onto the rumble strips! I held him off, finishing 3rd, about 21 seconds behind Jeff, and just 0.223 ahead of Kendall! I guess his front wheel was at my rear at the finish line, showing just how close it was.

I cooled off and shook hands with family and friends as we packed up and got ready for 14 hours of driving to get back to Michigan. I got my 3rd place wood and we were on our way.

Now I am on a 4 month hiatus from racing as things happen out west as well as schedules not aligning for me to race any sooner than Road America on the last weekend in July. In that time, I have a number of things I will be doing to my bike, including a new seat, front fender, paint job, possibly a new tank, new transmission, maybe Mirko's primary tensioner, fix a valve cover leak from the tach plug (I will probably just mod a cover to get rid of the tach drive hump entirely), new gauge mount (broke my Scitsu tack mount at NOLA this weekend), finish my box section steel swing arm and figure out a way to keep my sprocket drive bolts from loosening. I also have a number of other tweaks to make that I cannot even think of right now but by RA, it will look like fairly different than its current state.

RA in 136 days...
« Last Edit: March 13, 2019, 11:53:22 am by slikwilli420 »
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline bwaller

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #935 on: March 13, 2019, 08:18:25 am »
Well done Matt. Not sure if you tried to load pics, but they are a no-show!

You've put a few miles on to start the season.

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #936 on: March 13, 2019, 08:50:11 am »
Well done Matt. Not sure if you tried to load pics, but they are a no-show!

You've put a few miles on to start the season.

Thanks Brent! No clue on the photos, they are showing for me on my phone and PC. They are embedded links from Google Photos like I always use.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline gschuld

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #937 on: March 13, 2019, 10:18:09 am »
The photos didn’t load for me either😏.  Great write up regardless.

Offline turboguzzi

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #938 on: March 13, 2019, 11:33:37 am »
looks like you havent made them public in google

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #939 on: March 13, 2019, 11:53:50 am »
Never knew anything but public images. I shared them differently this time so hopefully it works.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline Tintop

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Re: CB750 AHRMA Sportsman 750 Racer - NOLA
« Reply #940 on: March 13, 2019, 02:54:37 pm »
That worked Matt.  Couldn't see them earlier, but can now. 8)
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #941 on: April 03, 2019, 11:47:19 am »
I have a number of changes being made during my mid-season break, which picks up in late July for a double weekend of Road America and Gingerman.

My original Scitsu tach mount sh*t the bed at NOLA, leaving me with a very floppy tach that was basically unusable, so I cam up with a much more robust version:



You can also see the Speedhut oil pressure gauge in the pic, and I need a few more pieces to mount the sensor then it will be ready to go.

I have also been meaning to add a front fender and had been looking at a few options from Airtech, finally settling on the one below. It will be mounted/painted for good once I pull the front wheel off to swap in my new Conti 3CR tires for the next rounds of racing.



I am also working on a different design of rear set plates that moves the master behind the plate and more out of the way, eliminating the long rod from the lever to master.

My last endeavor is going to be to figure out my transmission issues. At the end of both days racing at NOLA I was having the same shifting issues as I experienced starting at Barber last year. I am going to swap Kenny's 4 plate clutch back in and likely replace the entire trans with a new pro-cut one from him. I still do not understand what would make the clutch lever so loose once the bike was hot, but it was bad enough that to get the best lever possible at NOLA, I took my scrub lap right before my race and got the bike hot, adjusted the lever to almost no perceptible play, and at the end of the race, the ball on the lever was moving at least 1/2" before disengaging the clutch. This really needs to be fixed and for good, as it my have cost me a 2nd place finish at NOLA instead of the 3rd I got. I am open to any ideas that can help me understand my issue.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline turboguzzi

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #942 on: April 03, 2019, 02:02:11 pm »
check the diameter of the contis vs the avons. i rmemember having to adjust ride heights a bit when swithcing form avons to conti CR 2s to maintina same setup....

Offline Tintop

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #943 on: April 03, 2019, 03:53:39 pm »
I had a similar clutch issue with the sidecar's engine.  The issue with mine was the cam that pushed the rod had way to much clearance, allowing it to twist before it actually started to do anything.  This got worse as everything heated up during a race.  I ended up changing the clutch actuation mechanism.  I'd check the clearances in the actuation parts.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline Captain

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #944 on: April 03, 2019, 08:02:21 pm »
Have a close look at the end float of your main shaft and shim it so that the far bearing outer race is snug against the case. This will stop or reduce free play growing with heat.

Captain

Offline scottly

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #945 on: April 03, 2019, 08:12:45 pm »
I still do not understand what would make the clutch lever so loose once the bike was hot, but it was bad enough that to get the best lever possible at NOLA, I took my scrub lap right before my race and got the bike hot, adjusted the lever to almost no perceptible play, and at the end of the race, the ball on the lever was moving at least 1/2" before disengaging the clutch.
After the bike cools off, does the lever go back to almost no perceptible play?
Don't fix it if it ain't broke!
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Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #946 on: April 04, 2019, 05:05:46 am »
Have a close look at the end float of your main shaft and shim it so that the far bearing outer race is snug against the case. This will stop or reduce free play growing with heat.

Captain

With the shaft being adjustable I simply follow the manual and tighten until resistance the back off a little over half a turn. I could reduce this amount.

I still do not understand what would make the clutch lever so loose once the bike was hot, but it was bad enough that to get the best lever possible at NOLA, I took my scrub lap right before my race and got the bike hot, adjusted the lever to almost no perceptible play, and at the end of the race, the ball on the lever was moving at least 1/2" before disengaging the clutch.
After the bike cools off, does the lever go back to almost no perceptible play?

Yes as it cools the lever tightens back up and if I was too aggressive with my hot adjustment it will be completely tight.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline 754

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #947 on: April 04, 2019, 05:37:53 pm »
 I thought I went by memory and set a new engine up to1/8 or 1/4 turn clearance .. it was not enough , clutch started slipping 2 times before I read the manual and gave it 1/2 turn.  Too tight not good.
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Offline scottly

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #948 on: April 04, 2019, 10:11:06 pm »
I don't use the "tighten the screw until resistance is felt, then back it out xx turns" method anymore. Now, I check the free movement of the lever on the clutch cover with my finger, looking for about 2-3mm. If it needs adjustment, I loosen the locknut, adjust the screw, tighten the locknut, and check again. I've found that play in the hand lever pivot can exaggerate play at the end of the lever ball; with a worn clutch lever pivot hole and bolt, there may be over 1/2" of travel at the ball before the cable even starts to move...
It's curious that your adjustment loosens up with heat? This implies the clutch is moving away from the lifter cam in the clutch cover. Did you modify the cover to remove weight?
Don't fix it if it ain't broke!
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Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #949 on: April 05, 2019, 05:22:38 am »
I don't use the "tighten the screw until resistance is felt, then back it out xx turns" method anymore. Now, I check the free movement of the lever on the clutch cover with my finger, looking for about 2-3mm. If it needs adjustment, I loosen the locknut, adjust the screw, tighten the locknut, and check again. I've found that play in the hand lever pivot can exaggerate play at the end of the lever ball; with a worn clutch lever pivot hole and bolt, there may be over 1/2" of travel at the ball before the cable even starts to move...
It's curious that your adjustment loosens up with heat? This implies the clutch is moving away from the lifter cam in the clutch cover. Did you modify the cover to remove weight?

I did modify the cover but didn't remove any material from the ribs. I only removed the thread holes for the chrome cover. If the cover was flexing it should do it all the time. This is also a newer issue that appeared at Barber last year but never before then. Now it's toward the end of every race. The cover had been modified all season last year.
All you gotta do is do what you gotta do.

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