Topic: Salt Racer CB 750 OZ style

[johno]

Very important in Australia to have a "nickname"
mine is Johno,  Brian is Bear, Mick is retro etc so I traditionally look for a reason to make up a nickname for people,
ie captain Webber .....Scottly, or Billy Bling.....you know who  .... ... maybe its time I changed Bills to "Billy big balls"  your a motorbike slut Bill,  you'l ride any thing, any where, any time, but one thing for sure you seem to have less problems  with more Horsepower.  Just stay away from pushbikes and mini bikes 

[scottly]

I never said I was going to ride the damn thing, Johno!??  Seriously, my dyno is close to the same elevation as Bonneville.
Captain "Sparky" Weber.

[hotdog]

Very important in Australia to have a "nickname"
mine is Johno,  Brian is Bear, Mick is retro etc so I traditionally look for a reason to make up a nickname for people,
ie captain Webber .....Scottly, or Billy Bling.....you know who  .... ... maybe its time I changed Bills to "Billy big balls"  your a motorbike slut Bill,  you'l ride any thing, any where, any time, but one thing for sure you seem to have less problems  with more Horsepower.  Just stay away from pushbikes and mini bikes 

I call Benton in any correspondence we've had - "Billy the Kid".
Billy big balls sounds good too....ha...ha...

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[johno]

Scottly alias captain weber
Do you have air fuel sniffer for the exhaust ?

[Retro Rocket]

Scottly alias captain weber
Do you have air fuel sniffer for the exhaust ?

I've been trying to talk Scott out of sniffing exhaust fumes Johno, last time, he used his head as a landing pad  !!, No really, I saw the pics....

[Bill/BentON Racing]

Very important in Australia to have a "nickname"
mine is Johno,  Brian is Bear, Mick is retro etc so I traditionally look for a reason to make up a nickname for people,
ie captain Webber .....Scottly, or Billy Bling.....you know who  .... ... maybe its time I changed Bills to "Billy big balls"  your a motorbike slut Bill,  you'l ride any thing, any where, any time, but one thing for sure you seem to have less problems  with more Horsepower.  Just stay away from pushbikes and mini bikes  LMAO, if it's it's got a throttle, you supposed to twist it....WFO!  Let's ride! , Bill

[scottly]

Yes, Johno, my dyno has an A/F sniffer; I've learned the hard way not to use my nose anymore, as Mick has mentioned. I do not have an eddy current load cell, so I can't simulate loads such as wind resistance. While it's still early, let's not rule out the Mojave mile. Dennis, it would likely be the same distance as B'ville for you, as a guess?

[Retro Rocket]

Yes, Johno, my dyno has an A/F sniffer; I've learned the hard way not to use my nose anymore, as Mick has mentioned. I do not have an eddy current load cell, so I can't simulate loads such as wind resistance. While it's still early, let's not rule out the Mojave mile. Dennis, it would likely be the same distance as B'ville for you, as a guess?

Sorry mate, couldn't help myself...

[johno]

EXHAUST time.
Hi guys,
Started out repairing mellow yellow and got carried away with building a fleet of cb 750's to take to the lake.....hoping one makes the other end and finish line by stacking the odds.
MG750, AG750, MF1000.   are the 3 bikes.     it has drained my time and money etc so about halfway point with all 3.( billy 's influence)
For lots of reasons , some dumb  I have decided to run 3 different exhausts.

MG750 Mellow yellow is a complete new bike,  only the frame remains and that now has a replica CR 750 four mega's ( home made, was hard for me to find the 32mm ID pipe ( specs are primary 32 id x 530 long, megaphones are 32 id x 72 id x 850 long, suit yoshy cam at 10,500 RPM)

MF1,000 in with the big boys so just for a ride   Yammy frame with the old 1,000 sidecar motor with down draft ports. I have a yoshy replica exhaust on from mellow yellow

AG750, I am bought a pile of stainless 38mm OD (35mm ID) bends and about to make the exhaust,......4 straight pipes upswept, it will be hard to do the upswepts and keep the pipes narrow at the "boot position"    but thinking I just want to hear how they sound at full noise and planning to convert the bike back to a roady and a retro boardracer style exhaust and tank etc.
I am hoping there are a few exhaust techno's out there as I have read lots of books, googled away, bought software etc and every formula I have used for length has a different result.   Its a soft record currently held by a CB 750 chopper at 101 mph and I feel bad about trying to cut a bretherans lunch , but a soft record is just calling my name and so thinking the esxhaust is not so critical and want to give the straight upswepts a go.
So the forum can decide  on the length for me.    need it from valve seat to end of pipe.   the existing data is pipe material allready purchased so 35 id or 38 OD, std exh valve diam, max RPM 10,000, cam is 125/75 @ 25/56 so exhaust opens at

How long the pipe bro's                               ........ PS, get well Mike
cheers johno

[cbornotcb]

AG750, I am bought a pile of stainless 38mm OD (35mm ID) bends and about to make the exhaust,......4 straight pipes upswept, it will be hard to do the upswepts and keep the pipes narrow at the "boot position"    but thinking I just want to hear how they sound at full noise and planning to convert the bike back to a roady and a retro boardracer style exhaust and tank etc.

I WANT to hear THAT !
You know, the perfect pipe will be where your feet/legs/regulations say otherwise don't ya mate ?
Tiny

[bear]

Geez ya don't mind loading yourself up mate.
God help em on the lake when you retire, nobody else will get a run.

[Old Scrambler]

Johno............Some of my 'pipe' research says to try and match the size of the exhaust valve for a minimum of a few inches to as much as the length of the pipe.  Then allow the exhaust to expand which will help to scavange (reverse harmonic) additional exhaust as the valve is closing. For street use, a 4-stroke overhead valve motor performs well with a 736mm pipe (about 29 inches) before it releases the exhaust to the muffled expansion chamber.  That info closely matches the pipes on a Triumph twin and the factory pipes on a CB750.  The taper and length of the tuned megaphone for racing purposes varies but most current tuners prefer a small 'reverse' taper for high-rpm motors.

Shorter primaries tend to enhance high-rpm power.........especially when using 4 into 1 headers.  The most recent reading I have found is the use of a 'power-ball' (looks something like a US hand-grenade) in the primary exhaust pipe immediately following the collector. I have also read that some have had success when forced to use a larger ID pipe size, to insert a smaller size at the port-end (double-walled pipe) or at the junction with the megaphone.  A bend (or modest dimple-dent) in the header immediately after the 4-1 junction will act like a restriction.

Consensus favors the 4-2-1 design for street or road-racing. WFO favors 4-1.  Piston design, rpms and valve timing will also affect exhaust flow and should be considered for the final pipe design.

My pipe is a standard MAC that has been shortened to have only one small bend in the 64mm collector........then opens to a 100mm ID can with a 20mm reverse taper.  The design was encouraged by my dyno-tuner.   

[Tintop]

interesting post on another forum -

Can anyone help us find a 2007 and up Honda CBR 600RR engine assembly with all covers and injection bodies to loan. We are building an LSR = Land Speed Record chassis for a fellow in Australia and need the engine to build this chassis. Any help would be appreciated.

Compliments of the Season to All
Denis and Byron
CMR RACING PRODUCTS INC.
TRENTON AND BELLEVILLE ONTARIO
CANADA.

[cbornotcb]

Red cup racing ?

[johno]

I havent even seen another lsr bike since March, kinda living in my own world dicking around on mine. AND losing the plot ie

The super slippery rear end all turned to crap last week, the std front wheel conversion to rear didnt go how I wanted, turned out heavier than hell with the two large alloy adapters I made,  still  had no cush system as well and when  Frank posted he had a 75 F rear wheel on his bike so I checked out the back and found one, fell in love with it , great casting, light, strong, cush drive and was easy adapt to the cbr 125 rear disc, just had to machine 10mm off the drive hub to suit my early model driveshaft and all was good, except when I assembled it last weekend the extra width of the 75 F hub was wider than the front hub and didnt fit into the stainless swing arm I made.      your fault Frank, I am happy about the change though

So this weekend I will cut up the new s/s swing arm and widen it 3mm to fit it in and also I am waiting for some Titanium 12M x 1.25 x 30mm bolts to replace the std. drive hub studs as the studs hit the swing arm its so close.    pics when its done, been holding back on the pic cos my photobucket is nearly full.

[Tintop]

"........pics when its done, been holding back on the pic cos my photobucket is nearly full."

Johno easy fix for Photobucket, just start a new account with a different email.  That's what I did.  Most providers allow you to have multiple ones.

[Old Scrambler]

Johno...........SS swingarm........Ti studs..........Is this for all 3 bikes? Or will certain components like the wheels, seat, and front fender be common to each bike?

Will you have more than one rider?

[754]

Two large alloy adaptors.. Show a pic or diagram..plenty of ways to carve weight off them in most cases.

[johno]

Hi Dennis,
re the 3 bikes, two are mine one belongs to a friend.
Mellow Yellow 1 will be exactly as last year except for the brake pedal.
Mellow Yellow 2 will be same colour only, different tank , seat, swingarm, brake, carbs, exhaust etc
The mates 1,000 is the drag bike posted early in the thread  ( CB 750 engine in Yamaha frame) except the drag rear wheel is replaced with road wheel, it has the hi port head.
Enjoying it all but slows me down thats for sure,

Rider ?? not sure yet, my son is showing some interest but at this stage just 1 rider,  Jamie from last year as he is all qualified and experienced now and two support vehicles for the line up

Thanks for the tip tintop.

[Old Scrambler]

It must be getting a little WARM in your shop by now................just over 2 months to get ready

Unusually warm here so put off working on bikes to get more outdoor 'chores' completed. Will be travelling over the holidays and then get to work on a few mods to my bikes. 

[MRieck]

How are things going with the project Johno?

[johno]

Thanks for asking Mike,

I wont be racing this year 

It came to a head about Christmas time, I finished the 750 MG engine but not back in the frame, the spare 750 engine is half built only and the friends bike 1,000 sohc ( the old sidecar engine with hi port head) I finished the bottom end but the barrels had bad corrosion in barrels and he has to get  new sleeves which he didnt have the dosh so no bikes ready.  Mine It was time not money, work has been traumatic over the last 2 months and it blew my plans out the window.  just hanging in there !

I had a blood rush two weeks ago when Finny (suzuki 750 waterbottle record holder) phoned me to tell me he just finished two days on the dyno and both his motors ran well @ 122hp and 118hp spare.    Kind of challenged me but his HP doesnt intimidate me, its a big fat wide heavy bike and he has lost 5 engines over the last 3 years without finishing a run        so naturally I thought take mellow yellow and with a couple of weeks work it should get their OK ............then the next week #$%* hit the fan at work I have been working from 7am to midnight every day and my enthusiasm took a beating to the point it is too hard.

Lastly,  my next trip to the salt will likely be the last and after being humbled twice with lots of egg on my face the next time will be 3rd time lucky but as we all know you make your own luck and so I want to run the bike next time with the best possible preperation and a spare engine to hedge things my way.   I have worked on a plan B just in case Finny raises the bar in the 750 MG class to well over 150mph, there is a softer 750 class with a lower mph under 150 that I will run in, as I'm thinking 140 to 150 is the bar for me and all I need to run the class is alter the frame slightly to comply.

Work is usually fun for me but lately it appears to be getting in the way of my passion, I'm getting too old to save the universe, time to retire
ciao johno

[Bill/BentON Racing]

K, thanks for the update. Yeh, works been getting in the way for me too!! Glad you ok, you can do it! One day the record will be yours!!, Bill

[Jerry Rxman Griffin aka MuthaF'er]

Keep at it Johno. It will happen. You and Bill are obsessed. Me, I just want a strong reliable non-record runner. Well, 2 actually. Not giving up!! Dennis is on to something too but the 'damp' Salt has bit him in the ass the past 2 years.

You know, retirement is great or I should say mostly-retirement. I worked 400 hours last year BUT it has one draw back, it's those time/money lines crossing on the graph. Get yer Honda #$%* in order BEFORE you retire 

[Old Scrambler]

I was sooooooooo looking forward to the '3rd time is the charm' run on the salt. But I also understand that life can get in the way of having fun  

I have heard reports that you have thought about sending your bike (or motor) to the U.S. to be run at Bonneville..............If our BMST event is looking positive, should I bring a chassis?

Good Luck with your shop-time..........I am doing a little of that myself