Topic: Classic Bonneville Racer

[scottly]

Sorry guys, but it's not in the cards this year.

[richmagee7]

Hey Dennis,
How is it looking for you and BMST this year?  I know you have a lot of other travel plans but mother nature gave us last year off, so hoping to see you on the salt again this year.  Maybe bring that Jerry guy again if you do.

Rich Magee

[Jerry Rxman Griffin aka MuthaF'er]

Hey Dennis,
How is it looking for you and BMST this year?  I know you have a lot of other travel plans but mother nature gave us last year off, so hoping to see you on the salt again this year.  Maybe bring that Jerry guy again if you do.

Rich Magee

See you there Rich. Look forward to it as always.

[BomberMann650]

Maybe this year we will actually recognize each other!

Wake me up when its august 17th

[Old Scrambler]

The C.B.R. has a new cam to go with new valves and guides.........and a slight increase to the compression. So the plan is to go a bit FASTER

We plan to arrive on Friday AM to help with set-up for the event. This year the tow-vehicle will be a Jeep Wrangler. We are booked at the '6' and anticipate some fine Mexican dinners

[Old Scrambler]

I'm Ready

There's this road I know about 10-miles from Pocatello that is somewhat removed from weekday traffic. No fences or power-line poles, and only two driveways to adjoining wheat fields. My wife helped with the loading and unloading and made sure I had my phone for some unknown emergency. The CBR is a bit fussy to get started but after a few minutes of 'warm-up' I proceeded to traverse the cattle-guard and went for a 10-mile ride. The CX-7 cam has a noticable 'kick' at a little past 6000 rpms. I took it up to 9000 in 4th and just over 8000 in 5th. All went well and no leaks or drips. I pleasantly noticed that my left inner-thigh was much more heat tolerant due to changing oil lines for SS units which are slightly longer and allowed the oil-tank to be moved back and inward so my leg is no longer a 'heat-sink'

See you on the salt for BMST!

[madmtnmotors]

Best of luck Dennis, show'em how it's done! 

[Jerry Rxman Griffin aka MuthaF'er]

Time to kick some Triumph ass Dennis!!!  150 it is 

Frank, you guys in this year??

[BomberMann650]

BMST can always use more volunteers.
Especially ones with an immunity to boredom. 
(The 9th mile has a way of testing peoples minds)

I won't be racing.  My team mate and support truck is unavailable and I've yet to fire the motor.  The budget for battery, tires, suit'n'boots plus registration isn't there either.

So it'll be another year of shuttling about on my touring bike.  Which got another lighting upgrade!
Certainly helps with the pre-dawn trek out to the pits.

[Old Scrambler]

Thanks for the encouragement

Bomber............You should get some streamliner action this year

2 CB750 based bikes are expected at the SCTA event that starts on August 6th.....Both are 1000cc or more, one in gas, the other in fuel.
The fuel bike has also run at BMST at about 152-mph piloted by Bear from the Bike Barn. Both bikes have recent Cycle-X go-fast parts. Will George show-up this year?

[BomberMann650]

When i hear "streamliner protocol" come across the radio - thats when i know theres enough time for me to go poop.

Would be nice to see the 7 hit its stride - and bandits fun little cyclecar will be a treat.

[dragracer]

Time to kick some Triumph ass Dennis!!!  150 it is 

Frank, you guys in this year??

I initially had this event on my radar but somehow it dropped off.  Now i remember that we've got a Man Cup race the weekend of the 18th which might explain why i wasn't pushing myself to get to the salt. I'm hopeful that Dennis will continue to participate in this event in years to come so i can show up as support crew.

[Old Scrambler]

Frank.............It would be great to have you in the pits; but verbal support is always encouraging to this now 76-year-old racer. I already know that 2024 will be time for a lengthy trip to Alaska........so no to Bonneville for next year.

A few small things to improve on the bike include moving the fuel-tanks back about a 1/4-inch to increase hand-grip clearance, and repairing damage to the alloy supports on my seat that got rubbed by the rear tire when bouncing over the cattle-guard on the test run. Final fitting of the fairing will be next week. I plan to run 'open'- gas to begin and hopefully install the fairing and partial-streamline seat-tail section for gas and then fuel attempts. If all goes well the 'open' (naked) fuel run will be last and will save an hour or so of time to begin the tear-down process if new records are set

Several boxes and bins are required to hold all of the parts...........including small sealed tubs to keep the salt away from the carbs and the head. Last but not least is to carry 2 coolers for COLD beverages...........mostly for Jerry's benefit

[Jerry Rxman Griffin aka MuthaF'er]

All these years and the old man has finally figured it out    Except his spelling is lacking - Beernefit

[scottly]

I took it up to 9000 in 4th and just over 8000 in 5th.

What gearing are you running Dennis? If it's the same as when you had the dyno test in 2015, 8k in 5th is about 115 MPH. Was that the same gearing when you went 148? If it was, you were revving the engine 1000 RPM past the power peak at that speed (10,200), and need to subtract a tooth from the rear sprocket or something. Your target RPM is about 9200 RPM, plus or minus a bit. Also, did you refit the 125 main jets in place of the 120s you had when you were here, that were too lean?

[Old Scrambler]

Scott..............Yes, the jets are changed including new pilots of the same size due to 'hard rock' condition of the originals. Also converted all of bowl-fasteners to allen-head stainless.

After the dyno and test runs, I changed the sprockets from 16 x 44 to 16 x 42. I should have a bit of added power mostly from improved porting just below the seats and the new cam that has a more noticable 'kick' above 6000 rpm. I have 17 & 18-tooth options along with lower counts at the rear..........just in case I have under-estimated the power

It rained on the salt yesterday morning so the SCTA event is planning a 1 or 2-day delay.  That little moisture should actually help to improve the final course-grading. They have 7 and 8-mile primary courses prepared which is about as good as it gets The BMST tends to grade new courses at a slight angle of about 20-degrees to the SCTA tracks to smooth-out their tire groves.......especially those made by drifting and spin-outs

[BomberMann650]

Damn Scram that gearing is way off from my set up.
Are you using an oem sized rear tire?

Does suck the rain delayed speed week.  But also does not suck entirely

[MRieck]

Scott..............Yes, the jets are changed including new pilots of the same size due to 'hard rock' condition of the originals. Also converted all of bowl-fasteners to allen-head stainless.

After the dyno and test runs, I changed the sprockets from 16 x 44 to 16 x 42. I should have a bit of added power mostly from improved porting just below the seats and the new cam that has a more noticable 'kick' above 6000 rpm. I have 17 & 18-tooth options along with lower counts at the rear..........just in case I have under-estimated the power

It rained on the salt yesterday morning so the SCTA event is planning a 1 or 2-day delay.  That little moisture should actually help to improve the final course-grading. They have 7 and 8-mile primary courses prepared which is about as good as it gets The BMST tends to grade new courses at a slight angle of about 20-degrees to the SCTA tracks to smooth-out their tire groves.......especially those made by drifting and spin-outs

Did you bore the seat ID and blend the throat?

[Old Scrambler]

Bomber............120/70-18" with 50-lbs. AP when running on the salt.

Mike.......All seats were ground to 10-thou recess from original, then the intakes were blended to the 'bowl' after relieving some metal at the center of the air/fuel flow line. The valves were installed and the minor porting-seat work was done by LMR (Lindsay Machine Racing) in Salt Lake City.

A noticable change with the CX-7 cam is that now the motor is somewhat hard to get going and needs more time to warm up. I have the ignition timing set one-degree retarded from previous and may go more.  I have always used 110 gasoline but the supplier has changed and the oxiginated version is no longer available. Will explore Sonoco 116 and SR18 both of which have 'more power' but may need timing and jet changes.

[PeWe]

Port photos?
Detailed photos of ported CB750 heads are very interesting.
A kind of porn

[BomberMann650]

That tire size explains the gearing then.

Takes more gear to get speed from a 130 on 17's

[Old Scrambler]

PeWe...........If I set a record, I could take pictures of the ports

[scottly]

Bomber............120/70-18" with 50-lbs. AP when running on the salt.

To quote Frank more or less "Dude, that's not a tire, it's an O-ring".
Dennis, 42/16 sprockets is a ratio of 2.625:1, which isn't that far from a stock 48/18 at 2.66:1.
I would try the 17 front sprocket first with the 42 rear; this will give 2.47:1, and then if the tach is reading over 9500 RPM at the big end try the 18.

[BomberMann650]

Hey, Im not an impound inspector (thats gears' job)
But ..
The rulebook for classic mods only says it has to "retain the original engine heads, cylinders, and crank cases"

[Old Scrambler]

I have every sprocket combo calculated for ratio on my clip-board.........then numbered in sequence as to how close they are when compared to a 16 x 45 which gave me the highest speed to date.

The SCTA SPEEDWEEK event is holding tech at the historic Wendover airport. The salt is drying and current expections are for racing on course #2 on Sunday PM or Monday AM. Course #1 should be ready for Tuesday AM.........according to official's 'best guess'. The hot-rod car show is busy and I noted several new participants. A French entrant has a Wizzer-style bike with a blower that he hopes to set a record near 40-mph.