Author Topic: CB750 AHRMA Sportsman 750 Racer  (Read 171356 times)

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Offline kmb69

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #650 on: April 05, 2018, 01:06:58 PM »
clear nail polish, cheap, easily removable, easy to spot apply. 

I think Matt would look much more sophisticated with pink nail polish!  ;D  ;D  ;D

Enjoying your build Matt.  8)

Offline kmb69

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #651 on: April 05, 2018, 01:09:46 PM »
Especially loving that oil tank. It's the bomb!
Gonna have to make a similar one for my Automatic.

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #652 on: April 05, 2018, 01:11:32 PM »
how much practice and set up time do you have planned before the first meeting matt ?

Not nearly enough simon as in almost none. It will get maybe one chance to get on the street before racing. The first track I run this year is on a pretty desolate road so might be able to break it in a bit there as well. Beyond that, the Friday practice and Saturday morning practice sessions will serve as break in of the engine and re-acquaintance of man and machine for the year. There just isnt any track time in my area that I will be ready for.
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
« Reply #653 on: April 05, 2018, 01:13:35 PM »
Especially loving that oil tank. It's the bomb!
Gonna have to make a similar one for my Automatic.

clear nail polish, cheap, easily removable, easy to spot apply. 

I think Matt would look much more sophisticated with pink nail polish!  ;D  ;D  ;D

Enjoying your build Matt.  8)

Thanks on both counts Keith! The oil tank is at the weld shop for its second to last (hopefully) round of welding. It has been a lot of fun building it and it will have both great function and awesome aesthetics to it when complete.
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 simon#42

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #654 on: April 05, 2018, 01:26:41 PM »
how much practice and set up time do you have planned before the first meeting matt ?

Not nearly enough simon as in almost none. It will get maybe one chance to get on the street before racing. The first track I run this year is on a pretty desolate road so might be able to break it in a bit there as well. Beyond that, the Friday practice and Saturday morning practice sessions will serve as break in of the engine and re-acquaintance of man and machine for the year. There just isnt any track time in my area that I will be ready for.

i did think you where sort of leaving it a bit late , you are making a great job of that bike and your workmanship is first class but at the moment it is
only a collection of expensive parts . it wont become a racing bike until you have been on track three or four times minimum . you desperately need
dyno and set up time . even if you have to leave some of the detail nice bits like paint and polish get on track and do some testing !!!!!!

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #655 on: April 05, 2018, 04:49:02 PM »
how much practice and set up time do you have planned before the first meeting matt ?

Not nearly enough simon as in almost none. It will get maybe one chance to get on the street before racing. The first track I run this year is on a pretty desolate road so might be able to break it in a bit there as well. Beyond that, the Friday practice and Saturday morning practice sessions will serve as break in of the engine and re-acquaintance of man and machine for the year. There just isnt any track time in my area that I will be ready for.

i did think you where sort of leaving it a bit late , you are making a great job of that bike and your workmanship is first class but at the moment it is
only a collection of expensive parts . it wont become a racing bike until you have been on track three or four times minimum . you desperately need
dyno and set up time . even if you have to leave some of the detail nice bits like paint and polish get on track and do some testing !!!!!!

I'm with you but wishing for track time that doesn't exist won't really help. No it won't be perfect the first time out but if it goes better than last year it's a win. Dyno time is probably the better solution at this point to at least set up ignition and carbs.

Edit: there is a track day close on 5/19-20 which is two weekends before the first race. That would at least let me work some bugs out and familiarize myself with the bike again.
« Last Edit: April 05, 2018, 05:24:39 PM 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 Haybus

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #656 on: April 05, 2018, 08:08:31 PM »
Dyno is well worth it. You might get close with some road outings, but you need a stretch of road that allows you to really open it up a few times to see how she responds. BTW, hope you're running high octane stuff with those high comp pistons. I'm sure you'll get her done and be ready for the first outing, I have confidence in you. Can't wait to hear your delight from the first race weekend.

Alan

75 CB750
76 KZ900

Offline Rocketman

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #657 on: April 08, 2018, 03:11:11 PM »
A dyno with an air/fuel sniffer will let you dial in the jetting quicker and more accurately than reading sparkplugs.  I use a nearby go cart track to break in engines, scuff tires, bed brakes, etc.  Can't get out of first, but better than hiding from the local constables on public roads!  A local motard group runs there so the owner has no hesitation with motorcycles and only charges $20 for unlimited laps. 
« Last Edit: April 09, 2018, 05:41:52 PM by Rocketman »

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #658 on: April 09, 2018, 05:38:11 AM »
Dyno is well worth it. You might get close with some road outings, but you need a stretch of road that allows you to really open it up a few times to see how she responds. BTW, hope you're running high octane stuff with those high comp pistons. I'm sure you'll get her done and be ready for the first outing, I have confidence in you. Can't wait to hear your delight from the first race weekend.

Alan

Totally agree Alan, I'll see what I can come up with in my area, even if I need to drive a bit, it will be worth it. I will be running the 110 leaded from Sunoco this year.

A dyno with an air/fuel sniffer will let you dial in the jetting quicker and more accurately than reading sparkplugs.  I use a nearby go cart track to brake in engines, scuff tires, bed brakes, etc.  Can't get out of first, but better than hiding from the local constables on public roads!  A local motard group runs there so the owner has no hesitation with motorcycles and only charges $20 for unlimited laps. 

Martin, having something like that local sure would be nice but the dyno idea should get me really close.

With my small displacement change (736 to 760) will I really see too much change in jetting? Compression will be up but I am not changing the volume by very much, or am I way off?
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
« Reply #659 on: April 09, 2018, 05:43:55 AM »
This is where I ended yesterday evening. I don't have a clean cylinder to use to set the studs as Mike suggests, so I just put them in without it.



Before setting studs:


I did score a nice earlier cylinder from Eric (ekpent) which does not have all the dowel recesses on top near the head like later ones. Kenny prefers these with MLS head gaskets so there is a bit more surface area. Once I get the call from Kenny that pistons are ready, I will ship the vapor blasted cylinder to him for boring and ring gapping, and once back I will time-sert the m6 threads on top and notch the bottom of the sleeves to match up to my windage windows and it will be ready to start setting up deck height.

Last is my "finished" oil tank. It still needs some threaded bosses welded to the top so I can hang it with rubber isolators as well as a small drain back fitting that will come from the catch can.

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 napoleonb

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #660 on: April 09, 2018, 09:29:57 AM »
Looking nice!

Offline Captain

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #661 on: April 09, 2018, 01:14:21 PM »

Last is my "finished" oil tank. It still needs some threaded bosses welded to the top so I can hang it with rubber isolators as well as a small drain back fitting that will come from the catch can.



 Someone has been copying our oil tanks.............

 Captain

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #662 on: April 09, 2018, 01:19:20 PM »

Last is my "finished" oil tank. It still needs some threaded bosses welded to the top so I can hang it with rubber isolators as well as a small drain back fitting that will come from the catch can.



 Someone has been copying our oil tanks.............

 Captain

Borrowing with pride! You posted pics of the inner workings of your tanks and with your knowledge on the subject, I thought it was a great direction to take. Thanks for sharing some of that info with all of us. Hopefully you approve of my take on your great design.
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 Rocketman

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #663 on: April 09, 2018, 05:44:06 PM »
I am little help on how the changes you made will affect jetting.  Maybe some of the group with more experience in this area can offer their thoughts.

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #664 on: April 16, 2018, 07:13:10 AM »
Carbs should be back from Mike Nixon at the Motorcycle Project today. They have been completely gone through top to bottom and fitted with OEM Honda parts throughout, and should be about as good as stock carbs can be.

Kenny reached out and let me know that pistons should be shipping from Wiseco to him this week, so I will need to get my cylinder picked up from vapor blast and sent to him for boring and ring fitting. Once back it will get the 6 time-serts for the M6 head/cylinder bolts as well as relieved for the windage windows, then its ready for assembly time.

New billet cover from JLeather. I figured I needed something more stout than the flimsy stamped on so I don't destroy an ignition in a crash


I also picked up the frame from the weld shop after having a few braces added. You can see the small ones connecting the downtube and tubes above the engine, the one spanning the two down tubes in front and the one over the swingarm pivot in back. All mad from 0.035" 4140 tubing. The smaller ones are 3/4" and the larger ones are 1"





33 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 simon#42

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #665 on: April 16, 2018, 01:40:05 PM »
you mean 33 busy days !

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #666 on: April 19, 2018, 05:24:17 AM »
My side project of a roller starter is complete. I have not tested it on a bike yet, but have no reason to believe it will perform anything other than flawlessly at its job. It's borrowed from a few designs but its light, compact, easy to move and has a lot of torque. What's not to love??



30 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 gschuld

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #667 on: April 19, 2018, 06:15:16 AM »
Nice.  I’m curious, what did you use for the traction surface on the rollers?  It looks to be a section of adhesive backed peel and stick grip material we use commonly in boats.  Perhaps a fine line between nonnslip tire traction and something agressive enough to wear at the soft compound tire itself.

George

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #668 on: April 19, 2018, 06:31:34 AM »
Nice.  I’m curious, what did you use for the traction surface on the rollers?  It looks to be a section of adhesive backed peel and stick grip material we use commonly in boats.  Perhaps a fine line between nonnslip tire traction and something agressive enough to wear at the soft compound tire itself.

George

I went with skateboard grip tape. Its far cheaper than precut stair treads and comes in longer lengths. Its about 60grit if compare to sand paper. The starting event doesnt take very long so I suspect wear will be minimal. I have seen guys with expanded steel grating on their rollers, talk about tire wear. The bare steel rollers would be fine in all conditions except if I need to use it in the morning and its a bit wet out, the moisture on the tires/rollers might make it slip, but probably not with my big ass sitting on the bike. I don't have a kick starter this year so it HAS to work. Same goes for my brother.
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 calj737

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #669 on: April 19, 2018, 06:45:25 AM »
Aren’t you your brothers Kick Starter?  ;D

Roller looks great, Matt!
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline turboguzzi

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #670 on: April 19, 2018, 06:50:00 AM »
so you are talking the next month off from work?
:)

not that i see the whole picture, but from my experience looks like a good 100 hours of work left,

maybe start seeking some more hands to help now?


Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #671 on: April 19, 2018, 06:50:58 AM »
Aren’t you your brothers Kick Starter?  ;D

Roller looks great, Matt!

As long as he agrees to be mine!! Thanks Cal!
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
« Reply #672 on: April 19, 2018, 06:57:38 AM »
so you are talking the next month off from work?
:)

not that i see the whole picture, but from my experience looks like a good 100 hours of work left,

maybe start seeking some more hands to help now?

Nope, can't take work off, just continued diligence on my part and a very understanding wife. I get a couple hours a night, all day Friday after noon, and usually one full day on the weekend when Im not satisfying items on the honey-do list.

I have realized that some things will be good as is (like not finishing the welds on my oil tank) as they take precious time from things that NEED to get done. While I feel the pressure, plenty have started with less and gotten it done in 30 days.

It is indeed a collection of parts at this point, but minus the engine, the rest was run last year and proven to work, meaning electrical, suspension, fuel and braking have been fettled and are good to go. The engine is obviously the big question mark, but things have gone really smoothly thus far, and unless something just doesn't get here (waiting on pistons from Kenny and hardwelded rockers) it will get done. I figure another half day to finish assembling the engine, and another few hours to degree the cam. Wheels still need an hour or two each to true, and another hour total to mount/balance tires. Once its all there, you can assemble a bike in a long day. Its the little tiny things that pop up along the way that are killers. Hopefully most of that is minimal.
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 #673 on: April 19, 2018, 09:11:38 AM »
Matt, don't be shy if you need some extra hands
If it works good, it looks good...

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #674 on: April 19, 2018, 09:37:01 AM »
Matt, don't be shy if you need some extra hands

Will do Sean! Much appreciated!
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