Author Topic: CB750 AHRMA Sportsman 750 Racer  (Read 193553 times)

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Offline kmb69

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #725 on: June 04, 2018, 09:52:54 AM »
Matt, How did the weekend go?

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #726 on: June 04, 2018, 09:53:22 AM »
Hell of a weekend in the books!! We arrived Thursday to great weather in the area and got everything unpacked and set up to be ready for Friday practice. The bikes were both looking and working well, though road time had been limited to non-existent.

Friday came and I got the bike through tech and it was time to practice. I made it through practice #1 for the day and when coming through hot tech, I was told there was some oil on my tail piece. Well, he was being very modest, as the entire back half of my bike was covered in oil from top to bottom!!! We quickly started trying to find the source of the oil to understand where it was coming from. It was narrowed down to the oil tank, and its overflow tank. After making some changes, we went back out on the track for practice #3 on Friday. Well I ended up oiling a couple turns on the track and had to have a talk with the race officials. We decided to run a PCV valve that would keep the oil from coming back up the return tube that goes from the catch tank to the oil tank as we believed it was somehow creating vacuum and pulling oil. Well after a few runs with the new PCV valve in place, and the breather moved up near my leg so I could keep and eye on it, it was time for tech again. Of course I ran it a few times up a nearby road and saw nothing, until I pulled into tech. Oil coming out of the breather. Back to the pits. We decided to add another catch can to the system and move a few other hoses around. Tech blessed the new catch can made from a Gatorade bottle and we were done for the day.

Saturday morning tech came and went and the guys up there were ok with the fix and I was passed. I practiced and raced, with no oil issues all day Saturday. The race on Saturday had great weather, and a grid of 13 guys in my class. I was lined up on the last full row. When the green flag dropped, I wheelied the bike!! This thing makes gobs more power than a stock bike and I really need to learn to launch properly. Well we got one lap in and a guy had a little get off and we got the red flag, back to the hot pit area. Once there we were told it would take longer than expected to clean up, and to kill the bikes. Of course a lot of guys (including me) need rollers to start their bikes. So then we were directed to walk our bikes back to our pits and wait for the call from the officials. Well, being the smart ass I am, figured "why not try to bump start?" Well I did and it lit right up! I couldn't believe that I could bump start this beast but it worked and I was off to the pits. We checked fuel, and plugged the charger in for a minute just because. A few minutes later we got the call to get back to the track for a restart. I bump started again and I was off to the track, completing my warm up lap and settling on my grid spot. This time my launch was more controlled and put me in a great spot right with the group I was racing with into turn 1. I made my way around the track for the next 7 laps, passing a few in my class and trying to dice it up with the Superbike Middleweight guys, but they have the brakes to get me, despite my strong straightaway power, but it was fun to be aspirational. After the race, the first person I see is my wife Ashley, and she tells me I got 4th place!! A few guys in front of me went out with mechanical issues, but this is as much about skill as a rider as it is skill as a mechanic, and my mechanic skills held pretty strong that day. My personal best at this track before this weekend was a 2:02, and I was able to best that in practice, and really beat it down with a fastest lap in the race of 1:55.8!!! I was riding high, and still realize that there is a lot left out on the track, especially on my corner entry and braking points.

With everything squared away from Saturday, there as nothing to wrench on that night, so it was nice and quiet. Sunday came, and tech was no issue as I expected. Practice went well as we tried to dry the surface off after pretty intense rain overnight, but being race 8 I knew it would be dry by mid after noon and it was. My race went full length with no red flags this time, so it was a full 8 laps, hoping to beat a few of the fast guys out there and continue to show them the CB750 deserves to be in the class. My start was a little slow and it took me some more time to get comfortable compared to Saturday. Not sure what was off, but I just didnt "feel it" on Sunday. I had a few missed shifts on key areas and blew a few turns, having to make corrections to stay on track. Eventually I settled in on lap 3 or 4 and started putting down some fast laps. In fact, the last 3 laps were all faster than my best on Saturday!! I got to dice it up with Chris (Kickstart) for a couple laps and we passed each other back and forth, but once I found my groove, it was time to really dial it on. It was too little too late as I was unable to find any other guys in my group to race with, but I did manage a 6th and Im awfully proud of that, considering everything that went on that weekend, on and entirely new bike.

I did see some oil on the shifter cover side, and still need to investigate before the next race.

Road America is in 4 days and its just enough time to make a more permanent catch can and fix any of the oil coming from the shifter cover area, then its off to the races!!

Picture time!
All set up in the pits, ready to kick ass!!


Results from Saturday:


Me and Chris before Sunday's race:


Sunday results:


Great shot of me at speed:


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 #727 on: June 04, 2018, 10:17:11 AM »
Congrats! after a really great effort the matching results which you deserved.

Offline gschuld

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #728 on: June 04, 2018, 10:19:32 AM »
Nice job buddy!!!

Sounds like you will have a good season this year.  Strong engine, solid bike, less weight all around.

Thanks for the update👍

George

Offline voxonda

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #729 on: June 04, 2018, 11:40:58 AM »
WELL done, and the oil bid is all in the game.
Better sorry for failing then for the lack of trying.

Offline kmb69

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #730 on: June 04, 2018, 01:25:27 PM »
BIG KUDOS Matt. Awesome 1st outing!

Online turboguzzi

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #731 on: June 04, 2018, 02:34:46 PM »
7 seconds off is good progress! trouble is the next few ones is going to be sweat and tears...
bet a second disk would be worth 1sec a lap...

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #732 on: June 04, 2018, 05:33:16 PM »
BIG KUDOS Matt. Awesome 1st outing!

Thanks Keith!

bet a second disk would be worth 1sec a lap...

I'd kill for a second disc! For now I have to make do with one. It's a good one but nothing beats two.
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 #733 on: June 04, 2018, 05:44:51 PM »
hey Matt...couple pics of you and Chris on Sunday
20180603_145532 by Sean Barney, on Flickr
20180603_145540 by Sean Barney, on Flickr
20180603_145603 by Sean Barney, on Flickr
If it works good, it looks good...

Offline bear

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #734 on: June 04, 2018, 05:52:20 PM »
Well done Matt good result first up.

Cheers,
Brian
The older I get the faster I was.

Offline Old Scrambler

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #735 on: June 04, 2018, 07:17:46 PM »
Great Outing :) :) :) :) :)especially with a new bike ;) ;).............I'll look for you on Friday at RA 8)
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
CB750 Classic Bonneville Racer thread - http://forums.sohc4.net/index.php/topic,135473.0.html
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Offline 754

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #736 on: June 04, 2018, 07:29:14 PM »
Cool and well done.
 Does not everyone have to run the belly pan these days.
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It's All part of the ADVENTURE...

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Lost quite a few CB 750's along the way

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #737 on: June 04, 2018, 07:55:16 PM »
Great Outing :) :) :) :) :)especially with a new bike ;) ;).............I'll look for you on Friday at RA 8)

Sounds good!I love meeting guys from the forum.

Cool and well done.
 Does not everyone have to run the belly pan these days.

Some are just better hidden than others but we all need to have them. All classes. Going to redo mine for Barber to get it above the pipe.
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 #738 on: June 04, 2018, 08:33:49 PM »
Awesome, awesome, awesome. Glad you got it all together and had a great weekend. I too have had a bit of overflow problems with my motor. Oil running from the catch tank, down the inner fender, coating the swing arm and tickling the wheel, gets your attention right quick in the pits.  I've got it down to a bit too much oil volume, I think. I frequently check the catch tank after an oil change, after every outing. I get a few ounces each time, then it diminishes to nothing. How much oil do you put in a tank you built? Just enough, but not too much, ha ha.

Alan
75 CB750
76 KZ900

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #739 on: June 05, 2018, 05:59:27 AM »
Awesome, awesome, awesome. Glad you got it all together and had a great weekend. I too have had a bit of overflow problems with my motor. Oil running from the catch tank, down the inner fender, coating the swing arm and tickling the wheel, gets your attention right quick in the pits.  I've got it down to a bit too much oil volume, I think. I frequently check the catch tank after an oil change, after every outing. I get a few ounces each time, then it diminishes to nothing. How much oil do you put in a tank you built? Just enough, but not too much, ha ha.

Alan

Im in the midst of my oil change right now. I pulled the pipe to get the oil pan out and check in there for any crap. Well, there were shavings from the wheel that tensions the primary chains, but not chunks missing and it still looked pretty good. Oil was damn dirty though so good thing its getting changed. I pulled the pan to seal up the gasket and bolts there. I used a thin smear of Hondabond on both sides of the gasket as well as around the head of each bolt then torqued all of them down evenly. Did the same with the drain plug, thin layer around both sides of the washer and up the threads a bit. Im so GD sick of leaks, its making me lose the rest of my hair. I am going to pull the two plugs from the bottom of the engine and use thread sealant on those, as well as doing the rest of the main stud nuts. I did the shifter cover last night, and feel good about that.

I ran 4qt of oil in my system as the tank is a bit bigger and I have the oil cooler/lines. It gets it right to the bottom of the sight glass on the tank. I have a nice catch can that I will be using as a secondary on my oil tank breather as well that I need to get mounted. Pretty decent piece of kit, as it came with a bunch of fittings, a tube sight glass, a breather filter and some hose. I don't remember what I paid, but it wasnt much. Gotta love eBay.

I got my rear sprocket changed out last night as well. Road America is much faster than Gingerman, so went from the 46 rear to the 44 to get more speed. Going to need it too. I was about out of gear in 5th at the end of the back straight and Gingerman which is far shorter (1800ft-ish) vs the long straights at RA (3000 front straight and 2 other straights at about 2700 each). I did notice that I had some mis alignment of the chain Saturday and fixed that. Its strange because the swingarm pivot to rear axle distance was the same on both sides, but the tire was crooked and chain misaligned. I got one of those little Motion Pro chain alignment tools and got it fixed up. Going to have to go by chain tension and wheel straightness from now on, and not worry about the pivot-axle measurements.
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 livefast_dieold

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #740 on: June 05, 2018, 09:23:28 AM »
Congrats!!!

I was wondering about the second disk as well, I thought it was because of class regulations as the other guys have just one as well

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #741 on: June 05, 2018, 09:53:56 AM »
Congrats!!!

I was wondering about the second disk as well, I thought it was because of class regulations as the other guys have just one as well

Yes, limited to one period disc with 2 piston period type caliper. I chose an opposed piston design as most others have, but some use the 2 piston slider type so there is more room near the spokes. My uncle warped a rotor out there this weekend (using Yamaha FZR rotors) while I have the thicker cast iron which seems to be holding up really well. I dont get on it as hard as the really fast guys, but overall I am really happy with my setup.
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 Old Scrambler

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #742 on: June 05, 2018, 11:25:33 AM »
JMHO....The motor needs 3-qts plus a pint for the oil-cooler.........don't worry about the size of the tank or the amount of oil in it other than to make sure it flows........too much oil and you will see it in the catch-can or on your wheel ;) ........Its also a primary cause of leaking oil seals.......which means your dealing with a loss of power due to pressure.
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
CB750 Classic Bonneville Racer thread - http://forums.sohc4.net/index.php/topic,135473.0.html
'63 CL72 Project(s)
'66 CL77 Red
'67 Triumph T100C
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'77 750F2 Cafe Project
2020 ROYAL ENFIELD Himalayan

Offline livefast_dieold

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #743 on: June 05, 2018, 11:51:36 AM »
Congrats!!!

I was wondering about the second disk as well, I thought it was because of class regulations as the other guys have just one as well

Also, you got a really nice shade of blue for the tank, would you mind sharing the color code? I might consider it for a CB900 I'm doing

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer
« Reply #744 on: June 05, 2018, 12:26:38 PM »
JMHO....The motor needs 3-qts plus a pint for the oil-cooler.........don't worry about the size of the tank or the amount of oil in it other than to make sure it flows........too much oil and you will see it in the catch-can or on your wheel ;) ........Its also a primary cause of leaking oil seals.......which means your dealing with a loss of power due to pressure.

Sounds good OS, Ill keep it a bit lower when I fill up this time around. RA is a long fast track so getting air through the cooler wont be an issue.

Congrats!!!

I was wondering about the second disk as well, I thought it was because of class regulations as the other guys have just one as well

Also, you got a really nice shade of blue for the tank, would you mind sharing the color code? I might consider it for a CB900 I'm doing

Glad you like the color, but sorry no color code. Its actually a vinyl wrap over my whole tank. I think I may get it matched to a paint code and paint for next year. The wrap was a quick way to test a bike color, and Im really in love with it, so it stays.
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 #745 on: June 10, 2018, 01:07:46 PM »
well done on the weekends racing , you have got much closer to the winner this time , looks like you and the bike are making real progress
will leave you to tell the story !

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - RA update
« Reply #746 on: June 11, 2018, 08:42:05 AM »
I just wrapped up one hell of a good weekend!!

After Gingerman the weekend before, I need to address a few small oil leaks as well as get my oil tank breathing under control. I had a small catch can with sight tube and a bunch of fittings on the shelf for my street bike, so I was able to get things put together quickly and have a functioning catch can for my catch can. That system will get some revisions soon enough.

We got to RA Thursday afternoon and got set up and prepared for a full day of Friday practice. I wasn't that familiar with the track given my bad luck from last year, so a full day was welcome.

I was able to get to 3 of the 4 sessions on Friday and had expectations of lap times based on last year. Last year (stock engine, heavier bike) I was right around 3:30 a lap, and thinking that with the new bike and new lighter me, 3:05 to 3:10 was in sight. Session 1 on Friday resulted in a 3:15.7 as the hot lap. I knew there was a lot left on the bone out there and started really working on braking points and application, as well as position. If you have not listened to Ken Hill's pod casts on racing, you should as it was a wealth on good information for a newer racer like me.

Friday rolled on and I started seeing some more oil mist around the shifter cover and my stator plate. Between weekends I had pulled each main stud nut and coated threads and flange with thread sealer, hoping to rid myself of this issue. Well, it was still seeping from somewhere but was hard to tell where. I put and oil diaper between frame rails to both catch the oil and help find where it was coming from. I got back on the track with some new thoughts on how to get around fastest and the results started speaking for themselves, 3:11.2 best time for this round. I was going in the right direction but I knew there was a lot more there. Ken and his crew from Cycle X made the trek to RA to set up a booth and see my machine in action. What a great group of guys! They really knew their stuff. One of Ken's guys, Don, took a look and after about 2 minutes of staring, pointed to the rear #2 main stud near the stator plate, and said, there it is! I told him what I had done to fix it and he suggested teflon tape instead. Pressure was clearly pushing through the sealant and the thought that tape would hold that back made sense. I pulled the nut and cleaned everything up and applied some thread tape and retorqued. It was time for the next practice session after lunch. I have no clue where I ended on lap times for that session, must have missed taking a pic, but I was getting faster each time out.

Oil issue fixed, weather amazing, bike getting better and better, it was time for race day practice. This session I was able to lay down a 3:07.9! I was getting better and reflected on the day and day before on brake points, tip in points, brake application and body position. There was more out there, and I knew the bike could do it. I only did the one session as there as no need to beat up on the bike before the big show.

I started all the way on the inside of row 2, in the first wave. I knew a good launch could help me get out front and at least give me more of a shot to stay in play. Lots of fast guys on fast bikes were in the class and everyone was looking really good throughout practice. My launch was phenomenal and I was able to pull right in behind my cousin, riding a VERY fast Yamaha XS. He is nearly unstoppable but trying to keep up with him makes me faster and better so I tried my damnedest to stay close. While that didnt last very long, I knew I was putting down the fastest laps I ever had there. Eventually my uncle (current #1 plate holder for class, on an XS as well) got by me and he gave me another person to follow. He was chasing his kid out front and disappeared fairly quickly. I figured it was only a matter of time before I got picked off by other guys in my class. Eventually I heard the howl of a bike pull beside me and I realized that I was getting passed, but it was a guy from another class!! OK, I can live with that, but clearly he is faster than me, so Ill follow him and learn something. Well he got me nearly every turn and I got him back on nearly every straight, proving I had the motor that could pull really hard when needed. Laps ticked by and I only ever battled with him, keeping in mind that we were not in the same class, so no need to get too crazy. White flag, Im 3rd in my class! "Don't f*ck this up Matt! Just keep riding like you have been and get it done" is all I can think. I hit every brake point and every tip in point as best as I had all weekend. The bike and I felt great and as I pulled out of turn 14 to race to the checker, I didnt hear anything except the howl of my own bike, shifting at 10k, 3rd, 4th, 5th, checker flag!! A solid 3rd place, with #4 in the class about 9 seconds back. This was vindication that the bike deserved to be in the class and that it could compete at a high level there. It felt damned good. As soon as results were posted, I was anxious to see lap times. A best of 3:01.268 proved that when it was race time and there were people to chase and people chasing you, you can ride far faster than any practice session. My worst lap that race was a 3:02.883, proving that consistency was also in my favor throughout the race. Breaking 3:00 a lap was in sight, but I had another oil issue, this time from the pressure gauge adapter I was using. I new oil pressure was strong, and I cannot see the gauge when riding anyway, so I chose to pull it and use a small plug instead just to get through Sunday.

As Saturday wore on, weather became a hot topic. Rain was called for as well as colder conditions, neither of which I am wild about. Know that Saturday went so well, I decided to tech the bike again. If they were going racing, so was I! Well, it rained Saturday night, but by the time I got up in the morning on Sunday, it was done raining, or so we thought. I skipped the earlier practice session in the morning, deciding to do a later session right before lunch. We were race 2 again, so would be the first one after lunch, as #1 had run before the break. The bike felt good, but with a wet track, lap times weren't even worth checking, knowing I was off pace. It did allow me to check once more for any oil issues, which at that point, had been totally eradicated!!

Lunch came and went and it was race time. The track was dry and it had warmed some, so I knew that we would be on full race pace just as yesterday. One guy from the class scratched for Sunday with oiling issues, so I moved from #4 spot on the 2nd row to #3. I was right behind my cousin Nick, the guy to beat. A good start was again key, though apparently my brain took a short break. I was NOT ready for the start! Things moved faster than I had anticipated, so it was good that my shield was already down and I was able to get in gear and while my launch was a bit weak and a tad slow, I was able to grab a 2nd in the drag race to turn 1, right behind my cousin Nick. This bike pulls so damn hard. I cannot believe what an animal it really is. I was off and following Nick through turn 1, 2 and 3, keeping him in sight through the first big straight of the track, down to a hard left in turn 5. Execution on my part was the best it had been all weekend and I pulled so hard out of 5 that the front wheel got light as I shifted going up the hill. Turn 6 is blind so you have to have reference points to know when to brake or you WILL overshoot your turn. I had been working up to a really good speed for 6 and it paid off. I was finally able to drag knee through a turn and it was quite the experience. For whatever reason I had not been able to up to that point, but that little scuff at the apex told me I was going fast and technique was on point. Nick was in sight through 7 then another hard left into 8, which leads to the carousel of 9 and 10. This part of the track requires a high rate of speed but a long duration of neutral throttle. I had been working up to this one all weekend as well and it felt better each lap that passed. My weakest spot on the whole 4 mile course is the kink at turn 11. Too low a gear and Im redlined before standing the bike up on the other side and too high, it lugs. I favored too high as it was close to where the cam comes on for revs so it didnt really lug too bad. I was able to really get the bike howling after coming out of that corner, heading to 12, Canada corner. You are hauling a ton of ass down this part of the track and need to make full use of the brakes to get slowed for a 90ish degree right hander. Coming in too hot here blows the setup for the next corner (at least for me it did) so execution is key. I still had Nick in sight though he grew smaller and smaller by that time. His dad Jeff (my uncle) was close behind and pulled me somewhere in turn 11-14 on that lap. He points to his tail to get me moving and I knew I had someone to chase. Chasing Jeff the next couple laps pulled me even faster than I had gone on Saturday. There were a few points that a door was opened that I thought I could get him back, but they never materialized. I came in hot to Canada Corner and nearly went off track, but recovered and kept my position. Aside from chasing Jeff for a couple more laps, I never saw anyone else in the class. White flag again, and I was in third, but by how much I didnt know. Execution for the last lap felt good and very fast and as I crested the hill after 14 again all I heard was my own bike howling, crossing the checker for another solid 3rd place!!! I was only 17 seconds off the leader, and the next guy behind me was 23 seconds back!! I had competed a great weekend with 2 podium finishes. Again anxious to see lap times, knowing that giving chase to a faster guy would make me faster, I was blown away to see a fast lap of 2:58.846!!! Breaking 3 min there is quite an achievement on a bike like this, so I knew I had won the day in my corner of the world.

Congratulatory beers were consumed, but it was time to pack up and head home to Michigan. I got a chance to catch up with Old Scrambler after the Sunday race, and I always enjoy meeting another forum member. We discussed the finer points of the bike and I have a few ideas that I can mull over between now and Barber, only 115 days away!!

Overall it was such a great weekend and proved that I had built a competitive bike that deserved to play with the big boys. Letting the big dog eat at RA is the experience of a lifetime.

Awards ceremony Saturday evening:


Out there getting after it:


Drag race with Uncle Jeff!


Really laid over in a corner (get your toes up!!)


Jeff and I at full tilt:

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 kmb69

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Re: CB750 AHRMA Sportsman 750 Racer - RA update
« Reply #747 on: June 11, 2018, 08:48:40 AM »
Awesome weekend! Awesome report! Thanks

Offline MRieck

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Re: CB750 AHRMA Sportsman 750 Racer - RA update
« Reply #748 on: June 11, 2018, 08:56:38 AM »
I guess the suggested cam was working well in that engine. ;D
Owner of the "Million Dollar CB"

Offline slikwilli420

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Re: CB750 AHRMA Sportsman 750 Racer - RA update
« Reply #749 on: June 11, 2018, 09:07:50 AM »
I guess the suggested cam was working well in that engine. ;D

It roars like I didnt know 750 could!! It seems to be really working well with the 62mm pistons and at 6500 the bike comes alive! Id say it was the right call.

Watch for me at 0:09 seconds on the left. You can hear the difference between my uncle on the 1N Yamaha XS twin and my #237 four cylinder.

https://photos.app.goo.gl/apt8Cimebazn1Epa6
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