Author Topic: CB750 AHRMA Sportsman 750 Racer  (Read 177786 times)

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Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #400 on: May 30, 2017, 06:23:35 PM »
"I find that the fitting does not want to stay tight"
tight a small screw hose clamp over the nut and safety wire it to something solid, done.

Does the nut not have a safety wire hole?  AN fittings do.

It didn't but it does now. They are tired together so no chance of backing out. Exhaust is wired too as is the rear engine mount bolt that gave me trouble.

So close.

3 days...
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 - Final Countdown to Race Day
« Reply #401 on: May 30, 2017, 07:03:10 PM »
Go Willi go....
 Not sure if all An have the hole.. But warn that swivel fitting have a hole that is used to insert a retainer wire to hold nut in place.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline scottly

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #402 on: May 30, 2017, 07:24:34 PM »
What size master cylinder are you using with the opposed piston front caliper?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #403 on: May 30, 2017, 08:04:52 PM »
What size master cylinder are you using with the opposed piston front caliper?

12mm Brembo per the vintage brake chart. People swear by that chart so I figured it was the best place to start.
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 - Final Countdown to Race Day
« Reply #404 on: May 30, 2017, 08:11:27 PM »
Here is where the night wrapped up.

« Last Edit: July 11, 2017, 08:40:24 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 scottly

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #405 on: May 30, 2017, 08:45:15 PM »
What size master cylinder are you using with the opposed piston front caliper?

12mm Brembo per the vintage brake chart. People swear by that chart so I figured it was the best place to start.
Thanks. I'm looking forward to seeing your race report!! Good luck!!
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline 754

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #406 on: May 30, 2017, 10:37:46 PM »
Expect better engine down braking, with the charging rotor removed..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Rocketman

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #407 on: May 31, 2017, 05:47:26 PM »
Best of luck at Gingerman!  Stay cool and keep it on two wheels.  See you at Road America.

Offline livefast_dieold

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #408 on: June 01, 2017, 03:51:52 AM »
Good luck at the race!!!

Offline Haybus

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Re: CB750 AHRMA Sportsman 750 Racer - Final Countdown to Race Day
« Reply #409 on: June 01, 2017, 09:30:14 PM »
Well done Matt. Best of luck this weekend. Hope everything works well and you don't spend all weekend wrenching. Look forward to your report after your first weekend.

Alan
75 CB750
76 KZ900

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #410 on: June 06, 2017, 06:17:43 PM »
Tested the primary resistance of the coils on the bike and they are below the minimum threshold. Hondaman says anything under 3 ohms is bad. Both test 2.85. Another set I have tests about 3.2. Swapping to those awaiting a new ignition coming tomorrow. Heading out Thursday morning for RA.
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 scottly

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #411 on: June 06, 2017, 06:24:53 PM »
OK, that will work, too. ;)
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline scottly

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #412 on: June 06, 2017, 07:50:33 PM »
I would still run the resistors with the 3.2 ohm coils. Good luck! 8)
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #413 on: June 06, 2017, 08:03:50 PM »
I would still run the resistors with the 3.2 ohm coils. Good luck! 8)

Already installed! Just talked to Hondaman and he gave me the whole scoop. I should be all set now. Set of coils and ignition headed back to dyna after the weekend. Maybe they will let me get the 5 ohm coils instead?
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 Kickstart

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #414 on: June 08, 2017, 07:31:21 PM »
Glad you've got the coil situation figured out.. I think we both wrenched more than we raced last weekend.  :)

Hey, BTW, congratulations on successfully completing the class and officially participating in the races.  You and your father really worked for it last weekend.. way to pull it off!

I'm looking forward to seeing you down at Barber.

Good luck this weekend!
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - prepping for Road America
« Reply #415 on: July 11, 2017, 08:53:20 AM »
Alright, after fixing all of the photobucket issues (I am now using direct links from Google Photos) I figured I would update my loyal followers (haha).

All of my oil lines have been rebuilt with crimp fittings instead of compression style fittings. I also discovered that the fittings to the oil cooler were vastly UNDER-torqued. They required 29.5ft/lb and I was doing it with a small wrench before now, so that is also fixed up.

The last piece is the tank, which is what plagued me at Road America. It was originally Kreemed, but that crap comes out with acetone, so it will get a Redkote treatment, and a bigger petcock (5/16" Pingel vs the 3/16" stock)

That should cover all of my gremlins at least for now. For those going, I'll see you at Barber in October!
« Last Edit: July 11, 2017, 09:59:02 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 Kickstart

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #416 on: July 11, 2017, 09:41:14 AM »
What year tank do you have, and what model Pingel petcock works with it?

I have a 77/78F tank and finding a good flowing petcock has been a real challenge for me, as the original OEM ones aren't available anymore.  I can get an OEM one that fits, but is not for the 750 and doesn't seem to flow as well... and aftermarket petcocks are all junk.  I'm positive I'm going lean on long straights

I might switch over to a K2 tank I have laying around to solve the problem.
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #417 on: July 11, 2017, 10:02:46 AM »
One of two things you can do Chris. I also have a 77/78F model tank. The Pingel single output (or dual if you are keen on it) 5/16" will just fit into the tank bung. What I did was make an adapter to screw onto the tank and then the petcock will screw into the adapter. It moves the petcock down a little, but I still need to do some tweaking to get it just the way I want. If I didnt already have the single output Pingel, I would pop for the dual since you really can't have too much fuel.

The second option still involves an adapter at the bung, but I would simply use a 90 degree elbow to feed an auxiliary fuel valve. I thought about that but again, I already had the Pingel on the shelf so I figured I would try.
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 MRieck

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #418 on: July 11, 2017, 11:32:42 AM »
Install a good tank vent system with that Pingel.
Owner of the "Million Dollar CB"

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #419 on: July 11, 2017, 12:38:27 PM »
Install a good tank vent system with that Pingel.

Mike, talk to me about how good. I was fearing fuel issues at Road America and took my stock gas cap which has one 1/16" hole in the top and enlarged it to 1/8" as well as adding another. Meaning well over 8x the venting hole area of original. Do I need more?

PM incoming on a head I picked up.
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 #420 on: July 21, 2017, 10:43:27 AM »
Aluminum is a third the weight of steel. Chro-No is same weight as any other steel.
.120 sounds thin but would have to check a modern axle to compare.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #421 on: September 12, 2017, 06:13:23 AM »
Still alive and kicking and getting ready for a track day this Friday at a local track in South Haven, MI. I am familiar with this track so that takes some stress off and I can concentrate on technique and what the bike is telling me.

Only one pic to speak of, but its a big change. I received my tank from Air Tech, as getting the liner out of the old one was proving way too much headache and I would have changed to a glass tank anyway for next year. This is the Read Titan tank they make, Its a really nice piece, and about 9lb lighter than the stock steel tank, which is a plus in my book.

The tank has dual petcock bungs, but due to location, I will use NPT to barb elbows and run two inline shutoff valves along with a crossover which should totally rid me of fuel issues. The tank was coated by them and should last a lifetime with the non-ethanol gas I am using and the race gas I will use once my motor is built.

All of the other little odds and ends have been fixed as well, with new oil lines, a few changes to the wiring and a check of fasteners, oil, tire pressure, and chain.

If all goes well Friday, it will be pulled back into the garage, the gas drained, and aside from another wipe down and oil change, it will be ready for the big show at Barber.
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 seanbarney41

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #422 on: September 12, 2017, 09:43:16 AM »
What does Gingerman have to say about running vintage stuff at their track days?
If it works good, it looks good...

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #423 on: September 12, 2017, 10:19:27 AM »
Nothing whatsoever. 2-wheeled track days are handled by a place called Sporbike Track Time. This ended up turning into an event that will be an open format, meaning I get up to 3 hours of track time. Of course, by total loss ignition wouldn't have any of that so I figure 20-30 min on track and 30 min off to get battery charged up should be good.
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 seanbarney41

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #424 on: September 12, 2017, 10:39:50 AM »
So you have not contacted Sportbike Track Time to ask about potential problems they may have with you running a vintage bike?
If it works good, it looks good...