Topic: Turbo Charged CB550 Landspeed Attempt

[BomberMann650]

Update on race bike;
Theres a rotary club car and bike show coming up so i got busy on a few little things.

Firstly, tires and wheel bearings.  Nothing too luxurious.  The road classic tires offer high speed ratings in the sizes i needed.  Put in the required metal valve stems and measured amounts of dyna balace beads.  By measured, i let the shops electronic balancer tell me how many grams to put in.
I didn't go for broke on the wheel bearings.  Just the standard service kits for each of them.  But did take care to open the seals and fill with the right amount of grease.  Removed the gear from the front wheel speedo while things were on the bench.

Now the fun stuff.  Since i last ran the engine.  The AFR meter (and engine) pinged at 17:1 with a free revving partial throttle show off.  So the needle taper was no good for this setup.  Contacted mikuni and they recommended a methanol needle for boosted application.  I also picked up a super rich profile for NA applications, will see what makes the motor happier.  Then upped the main from 110 to 120 so it hopefully it will be able to take some boost

Also, more importantly, ordered a leather suit and gauntlets.

[HondaMan]

Also, more importantly, ordered a leather suit and gauntlets.

A man after my own heart!
I still have (and use) mine, Brooks leathers (with the dual white stripes) in the original 750 sandcast's blue-green color. Love the fit! They expand at both arms and the crotch of the pants.

[BomberMann650]

Also, more importantly, ordered a leather suit and gauntlets.

A man after my own heart!
I still have (and use) mine, Brooks leathers (with the dual white stripes) in the original 750 sandcast's blue-green color. Love the fit! They expand at both arms and the crotch of the pants.

I didn't get anything that fancy - just an affordable one-piece that should have enough dead animal hyde to pass inspection.
Sometimes gotta wonder where these apparel companies are finding their humanoid models.  The noru gauntlets fit my meaty paws, but i may have to torch the fingertips to shorten the buggers.
Clearance priced at $24 and i still have my old joe rockets if the nice new gloves annoy me too much.
Now the issue is, do i bother getting a proper race helmet, or just toss on my basic street helm 🤷🏼‍♂️
Either way, early registration should go active in the next 90 days.  Plenty of time to hesh out the technicals on the bike.

Sadly my team mate and co-builder had a stroke and won't be able to come to the races.  Was really counting on him to drive the support truck.
So I'll have to get an "in memory of damnit df farva" sticker thats says "he's not dead, just wish he was here"

[BomberMann650]

Just my luck, out three motorsickles in the show i placed fourth 😆

[BomberMann650]

I hurt myself today.

Weeks of zero tracking info and feeling scammed.  Then all of a sudden a box shows up on the porch.
Now i just feel big and fat.  Torso length pinches my balls and crushes my shoulders. Can't even get my other arm into the suit by myself.  Which i doubt would make things any more comfortable.

For the price, i was surprised it had some Alpinestar pieces snuck into the construction.

Don't even know if it would fit my teammate, cause he's not here to try it on.

[grcamna2]

I hurt myself today.

Weeks of zero tracking info and feeling scammed.  Then all of a sudden a box shows up on the porch.
Now i just feel big and fat.  Torso length pinches my balls and crushes my shoulders. Can't even get my other arm into the suit by myself.  Which i doubt would make things any more comfortable.

For the price, i was surprised it had some Alpinestar pieces snuck into the construction.

Don't even know if it would fit my teammate, cause he's not here to try it on.

I hope they swap it out for the correct size.

[BomberMann650]

It's not worth the oversized international shipping Grcamna2.

Best bet is to try and fence it to a local squid or hand it off to the buell bros for the experience program.

[johno]

Very important to get the torso length correct. The Crown Jewels must be protected at all costs, spare no expense.

[BomberMann650]

Huge Update on the project!

The Dyno Session Happened - and the turbo spooled with ease.
Main Jets were increased several steps.  Getting it ready to go wide open with more boost potential.
Oddly, after all the work, the cam, the smart ignition - the dyno is sampling a modest 37 rwhp.
Will attribute this to the lowered compression ratio.
But its tearing through the gearing up to redline and 125mph

Also, ordered a used suit from a heavyset seller on ebay.  Should be here soon, hope its a better fit.

Video to follow.  Headphones recommended

[BomberMann650]

Turbine Blended with an inline four is a hell of sound

[denward17]

Wow!, that's impressive.

[BomberMann650]

Hit the home depot early this morning for some plumbing.
An experiment to determine if an intake runner would encourage fuel flow above 3/4 throttle.
It didn't - marginal improvement below half throttle - calmer idle.
37 rwhp on a turbo engine isn't much to brag about.  But for a half throttle run with low boost pressure - theres a chance adding a thunder jet will unlock the potential.

Either way, even a little boost sure excited the old girl.  I don't recall the stock bike going from 5-9krpm this quick before

Still ran it up to 10k for another sampling.  The wheel speed is there.  Could surpass the existing 550 record.  Might need to swap rear sprocket to back up a 125+ qualifier.

[scottly]

Where is the AFR on the chart? Plotting RPM instead of MPH might be more useful. How much boost were you running? 37 HP is pretty pathetic.

[scottly]

It looks like the rear wheel is bouncing on the drum at the shift into second gear?? If the tire is slipping on the drum, it can cause the spikes in the graph like yours shows.
Here is a chart where the wheel started slipping on the drum as the engine got close to the torque peak; notice how erratic the torque curve is towards the end of the pull.

[BomberMann650]

Where is the AFR on the chart? Plotting RPM instead of MPH might be more useful. How much boost were you running? 37 HP is pretty pathetic.

I know 37 is lame since ya'll got NA motors makin 45-70 round here. 
Averaged around 3 psi boost for this initial session.  Not a lot, but it spools pretty quick.  At this stage, the motors not benefitting from the boost much.

We used my on board wideband for tracking AFR - the sniffer tube from the dyno wasn't gonna work with my left side dump pipes.
The clamp on tach was pretty useful.  Allowed me to see idle rpm and make sure ignition is rev limiting.
Since this isn't fuel injection tuning, it was just more fun to print the wheel speed.  For y'all's benefit 125 mph is around 10krpm.  That will change when i add gearing to the sprocket

It looks like the rear wheel is bouncing on the drum at the shift into second gear?? If the tire is slipping on the drum, it can cause the spikes in the graph like yours shows.

I noticed a little bit of wheel hop while reviewing the footage.  Haven't even begun to adjust the suspension dampeners.

Some of variation on the chart is my working the throttle to maintain a steady afr.  Hopefully won't have to do that once the thunderjet circuit is installed.
Once the extra jet is flowing, will try increasing boost pressures. 

[BomberMann650]

Been a while since the dyno appointment.  So an update on the 550 turbo project.

Took the tank off to line with eastwood sealer.  Discovered the petcock had developed a leaky valve and replaced that.  How and why it sprung a leak is a mystery. Bypassed the fuel pump and ran a new section of fuel hose.

Installed the thunderjet into the carburetor, took the big 'n rich main jet down to something a bit more sensible.  Sent a pic of the tj setup to the lead tech inspector and was indormed that would also need a fireproofed fuel hose. 

Went through the vacuum lines on the turbo gate, sensor, and pressure meter to make sure nothing was broken.  And sure enough, found a loose connection.  Explains the initial 37hp test result.  Acquired some more reliable wastegate springs.  So should i turn up the boost.  I won't be guessing which spring is what.

And i put a 35t rear sprocket on.  With the 18t front and 10,000 - the machine could achieve some respectable speeds.  Provided the adjustments to the rear shock remedy the hop.  The preload and rebound settings were turned down waaay too low when it hit the dyno.  At least the cantilever link allowed a simple ride height adjustment.  Had i known the bikes potential to sag under acceleration i may have built more tire clearance into the tailpiece.

BMST is coming soon.  The bike os registered, i borrowed a suit from a fellow racer and have the necessary race pit equipment ready to go on the transport trailer.

2024 lets go!

[Don R]

 Do you feel like the float bowl is staying full? That's one thing the turbo drag bike guys warned me about. Of course, you have a better carburetor than the old Harley carb.

[Jerry Rxman Griffin aka MuthaF'er]

See you on the Salt

[BomberMann650]

Do you feel like the float bowl is staying full? That's one thing the turbo drag bike guys warned me about. Of course, you have a better carburetor than the old Harley carb.

The hs40 is a pretty big carb for a 550four - considering it came off a harley with more than double the displacement!
It was Runnin on the dyno without the fuel pump active.  The holley pump i got would overwhelm the float needle and I haven't been motivated enough ($$$) to change it out.
Since the dyno runs weren't exactly long in duration.  If I get on the dyno before the races, i'll try holding it open for a minute and see if there could be an issue. 
That said, each time i changed jets it drained out a healthy volume of fuel.  In spite of gravity forcing fuel through the pump at an odd slope.  It may flow more freely with the hose making a direct dive to the carb.

See you on the Salt

Hell yeah! 

[Old Scrambler]

Petcock flow-capacity is important

I'm packed and mostly ready.

[BomberMann650]

I'm packed and mostly ready.

I'm mostly packed and not even sure im ready for this.

It dawned on me last week, I've never ridden a turbo bike.  Much less a turbo bike on salt 🥴🥴
People ask how i think the run might go.  And the only honest answers are

"Either i cross the finish line, or I dont."

[BomberMann650]

Wake me up when its time to race

[grcamna2]

How's the bike running ? 

[BomberMann650]

How's the bike running ? 

Yes 🤷🏼‍♂️

It spends its days at rest on the paddock.  Test fired last week to show a friend.  But thats all for now

[Old Scrambler]

I'll see you on Friday & Saturday...........Keep your batteries charged and your beer cold