Topic: CB750 AHRMA Sportsman 750 Racer

[Kickstart]

Sounds like there is plenty for both of us to do!

I look forward to meeting a fellow SOHC'er as well. You're in Sportsman 750 as well right? Did we find that we met at Barber or no? I walked around with my uncle Jeff Hargis trying to find any 750/4 we could to check out.

I just talked to the body shop and they will paint all three pieces for $200. Nothing fancy, just a single color, down and dirty.

The frame goes to the welder one last time for rear sets and belly pan tabs, as well as the oil tank which is getting some safety wire tabs. I may be going a bit crazy on safety wire, but I am taking the rules to heart and I don't think anyone with have an issue with a little bit more safety wire than required, rather than any less.

I am so close I can taste it, but I know something is bound to pop up, but I do still have a few weeks, so if I can keep working on things every day, I'll get there with time to spare.

30 days...

Yes, I'll be with you in the sprotsman 750 class.  It's a pretty competitive class... at lease it feels that way, especially since I have a stock engine.  I feel like we have more grunt off the line and out of corners but just don't have enough HP to keep up with a lot of other bikes on the straights.  That said I think Gingerman is a tighter course, so maybe not as much an issue.  Speaking of which, I'll probably start off with 17/48 sprockets and see how that feels.

Yes... I believe I met you and your Uncle at Barber... what's your race number?  I'll keep an eye out for you when I get there (my number is (171)

No one will complain about you having too much safety wire... you don't want to be "that guy" that oils the track.

Good idea planning to be done a week early... something always comes up.  I'm pretty confident I'll have the 750 ready for Gringerman but I'm still doing some engine work on my 160... so it's definitely crunch time for me as well.

For the 750, the only major thing I want to do is replace the stock K2 rotor with a lightened one.  I ordered one from CycleX... hoping they're as great as they say they are.

Besides that, just need fresh oil, gas, brake fluid, and maybe fork oil... and to slap on some new rear shocks.  I got some DSR Works shocks ready to go.  Last year I was having a lot of trouble with the bike wobbling between turns 10 and 11 at Barber.  Working with the Racetech guys there, and after playing with the valves, our best guess is my rear shocks are too stiff.  They're iKon shocks off my street bike... and after dropping weight down to approx. 400 lbs they have almost no sag.

[Kickstart]

I will be at the gingerman race too.  Spectating both you guys...and running home for spares when you break #$%*...or drink em all lol

Sean, it will be great to see you again!

[slikwilli420]

Im 237 Chris. I will be caravan-ing with my uncle and some of his other Sportsman 750 buddies. Planning on getting there late afternoon Thursday to get set up. I am doing the class all day Friday so it should be quite a spectacle!!

[slikwilli420]

Final assembly started yesterday. Things are fighting me but are also moving along. Still fabbing things as I go.

Freshly painted frame and swing arm



Getting things bolted up. Wiring is on and engine is in along with other major pieces. Doesn't feel as futile but still lots to do.



19 days...

[slikwilli420]

Might need to fly you and Bill up to burn the midnight oil! Things are looking good and I'm checking things off the list.

Here is where tonight ended.

[slikwilli420]

Small victories tonight. Rearsets mounted and fitted with linkage that works pretty well if I do say so. I need to play with the shift linkage arm alignment to get them perfectly parallel but I was able to get through all the gears easily.






18 days...

[Haybus]

Quit copying me!!! Ha ha, just kidding. Looking great, seriously. I have those same rear sets and the offset on the shift arm gives you a bit of throw for shifting. You look fairly balanced, so you might have a bit more foot movement than you might want. I was having to really make positive shifts with a lot of foot action to keep from hitting false neutrals. I made an arm with a few holes so I could play with the throw. I ended up using the smallest distance and like the minimum amount of movement it takes, though it's a bit harder to find neutral. Probably wouldn't change it now that you're in the final throws, but pay attention to shifting when you're racing. Might be me and work out just fine for you.

Alan

[slikwilli420]

Matt - why not use an offset arm that allows the shift rod to be straight? I believe Fast From The Past sells rear set components and has them.

You thinking something like this Cal?

http://www.fastfromthepast.com/01-0082

I could also modify a stock shifter pedal and try the same thing. My current set up seems to shift nicely but I won't really know for sure until I am riding the bike under load. I could change the linkage arm to steel as well just to reduce flex.

[bwaller]

Just two thoughts surfaced in my fog and I'll mention them but you can take with a grain of salt! 1) your pegs are nice & new but kinda long?? Simply don't crash and all will be groovy! Otherwise those hard parts dig in and either bend along with their attachments, break off or catch and start the bike flipping about. You don't need all of that peg, I'd shorten them. 2) Consider a GP shift arrangement. This will eliminate linkage plus an alloy shifter that will break. You can drill holes galore in a steel shift lever than can be straightened easily.

It looks good man and you can make changes anytime if you see fit, so don't hate me!

[slikwilli420]

Just two thoughts surfaced in my fog and I'll mention them but you can take with a grain of salt! 1) your pegs are nice & new but kinda long?? Simply don't crash and all will be groovy! Otherwise those hard parts dig in and either bend along with their attachments, break off or catch and start the bike flipping about. You don't need all of that peg, I'd shorten them. 2) Consider a GP shift arrangement. This will eliminate linkage plus an alloy shifter that will break. You can drill holes galore in a steel shift lever than can be straightened easily.

It looks good man and you can make changes anytime if you see fit, so don't hate me!

No hate at all Brent. I will definitely be shortening the pegs by a bit. They long even for street pegs. I have thought about GP shift, but I need to try it in the off season when I can concentrate on it until it embeds itself in my brain.

[Tintop]

I got around the 'it's GP shift stupid' part by putting a piece of tape up front with a #1 and a big arrow pointing forward (up). Might slow you down a bit to start as it become natural; but the simplified shifter, and longer term benefits are worth it.

[bwaller]

I still struggle with the back n forth between GP, non GP. Oh yes there have been downshifts at WFO throttle too. That's where good valve springs and seat pressures are important. 

Then there's Dave Roper. I've seen Dave hop from GP to regular left side shift. then a British bike with GP right side. Made me feel like an oaf!

Sorry Matt, back to the program.

[slikwilli420]

SUSPENSION SHIPPED TODAY!

Going to be out of town the next day but will get back to it hard this weekend. Should see race tech goodies Friday.

[slikwilli420]

Good day of wrenching.  Race Tech stuff showed today and just needs to be installed.

Wiring is totally complete. All the switches (kill and main) work as well as the ignition being installed and timed.

I am still struggling with a design for fork stops but have some materials to make something happen. The last piece is getting the tank painted.

As of now the bike should run with gas and oil.

14 days...

[slikwilli420]

All geared up! Guy said the suit was a perfect race fit.



Race Tech! This stuff will be the primary focus tomorrow.

[gschuld]

You are lucky that you can fit in off the shelf suits.  Apparently, my shoulder to crotch length was too long for off the shelf stuff to fit properly(I'm pretty tall and that is not the place to be constrained, trust me)

That custom Vanson vo93 two piece suit cost more than my first 2 Honda CBs combined. . It's nice though.

George

[Haybus]

Looking good. If you haven't already planned for it, I would suggest an inner rear fender. Mine is build from a $10 plastics garbage can held to the frame with rubber sleeved conduit clamps. Keeps from flinging stuff at your oil tank and carbs.

Alan

[slikwilli420]

Good call. I need to come up with something.

[seanbarney41]

guessing you whacked the tabs for the stocker...I think it would still be easy to make fit and its light. 

[Tintop]

guessing you whacked the tabs for the stocker...I think it would still be easy to make fit and its light. 

that's what I did, then later realized I needed them.  Just reinstalled using zip ties, never had an issue.

[slikwilli420]

So I officially have a running race bike!

A couple small (hopefully) issues were some carb leaks which I suspect are float needles that need cleaning which shouldn't be too big of a deal.

A more pressing issue is what sounds like can chain slap. Initially I thought it was the rockets but I checked each one and they were fine. I did do the can chain tensioner adjustment but I'm still getting a lot of what sounds like chain noise.

I will pull the tensioner tomorrow and make sure the spring and plunger are working properly but beyond that I'm not sure what else I can check.

Thoughts?

[Jerry Rxman Griffin aka MuthaF'er]

Carb sync

[slikwilli420]

Bench sync out with vac gauges?

[754]

Anyone looking for the rubber covered clamps, Adel clamps I think they are called.
Congrats on getting your beast  fired... Hope you have fun...

 You can synch pretty close with a rod, I can run you though a pretty accurate method.

[Haybus]

The tensioner shaft can get a decent burr from zealous tightening of the bolt, which could (??) lead to a bit of stiction preventing the light duty spring from doing its job. Pulling the tensioner and cleaning is certainly the safe bet and hopefully the cure. I give the tensioner arm a bit of help with a small screw driver to make sure it isn't stuck. Also, there's a procedure for proper adjustment, documented in Hondaman's book.

Alan