sirbike
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I’ve been encouraged to post this.
So with all due warning that you may die a similar death as those darksiding, here we go. Proceed at your own risk.
2008 CBR1000RR
Wheel
ST1300 axle
CBR left axle spacer
Right side spacer machined 1.35mm longer than stock CBR spacer
EBC Pro-Lite XC Contour Front Brake Rotor Honda CBR600RR 2003-2026
Titanium right side brake disc bolts
Notes
The distance between the CBR discs is 3mm less than the ST discs.
This generally brings the discs very close to the inboard surface of the slot for the disc in the caliper brackets. That’s 1.5 mm displacement within each slot. One small area needed the slightest sanding to clear the disc.
Given the direction that the sliding calipers move with pad wear this does not appear to be a problem.
Mounting the discs on 1.5mm spacers would tidy that up.
Not finding proper spacers, I looked at washers as spacers but variance in thickness bothered me.
I may revisit this but there appears to be no functional issues.
During the prototype installation the abs light would come on any where between 50 to 250 miles.
The steel disc bolts run close the ring sensor. After installing titanium bolts there has been no issue since.
The sensor ring took some grinding to fit around the disc bolt heads.
Holes were drilled and tapped in the disc carrier to receive mounting bolts for ring.
Regarding the abs.
The front wheel is spinning 6% faster. It’s something to consider.
The abs seems rather granular looking more for lock up to release rather than a subtle speed difference that would require more readings per second.
I base this on the small patches of rubber marks on the ground when braking hard enough to activate the abs.
Anyhow, the wheel has 6% less leverage over the brakes. That translates to about that much less effort at the brake lever to achieve the same braking.
Stainless lines give excellent modulation by way of a more direct connection between the hand and the calipers.
Why did I do this?
I was chasing a Miata up a twistie valley road that crosses the Back of the Dragon and with suspension upgrades, DMR front cartridges Penske shock, the bike felt greatly improved yet still ponderous beyond the simple explanation of being a heavy bike.
The geometry is not that much different than a Blackbird.
The 17” front wheel makes a huge difference.
It is 5.5 pounds lighter and with the half inch shorter radius the gyroscopic inertia is greatly reduced.
Hard mounting the handlebars to the triple clamp properly connects them to the front wheel for a precision feel.
The 1/2” shorter radius and the Penske shock extended just enough for the axle to clear the muffler and the result is a bike that changes direction very easily. It will pretty much stay in the turn until input otherwise is applied.
At the same time I moved up to premium suspension telling Traxxion to give me the best handling possible across twistie Appalachian roads in various conditions using AK20 cartridges and the Penske double clicker, I am willing to sacrifice comfort.
It handles great and 500 mile days are fine.
My other ST is set up for very comfortable 500+ mile days.
The most fun description of the bike was willsmotorcycle after riding PA route 666, saying,
“Dude, this isn’t an ST1300”
So with all due warning that you may die a similar death as those darksiding, here we go. Proceed at your own risk.
2008 CBR1000RR
Wheel
ST1300 axle
CBR left axle spacer
Right side spacer machined 1.35mm longer than stock CBR spacer
EBC Pro-Lite XC Contour Front Brake Rotor Honda CBR600RR 2003-2026
Titanium right side brake disc bolts
Notes
The distance between the CBR discs is 3mm less than the ST discs.
This generally brings the discs very close to the inboard surface of the slot for the disc in the caliper brackets. That’s 1.5 mm displacement within each slot. One small area needed the slightest sanding to clear the disc.
Given the direction that the sliding calipers move with pad wear this does not appear to be a problem.
Mounting the discs on 1.5mm spacers would tidy that up.
Not finding proper spacers, I looked at washers as spacers but variance in thickness bothered me.
I may revisit this but there appears to be no functional issues.
During the prototype installation the abs light would come on any where between 50 to 250 miles.
The steel disc bolts run close the ring sensor. After installing titanium bolts there has been no issue since.
The sensor ring took some grinding to fit around the disc bolt heads.
Holes were drilled and tapped in the disc carrier to receive mounting bolts for ring.
Regarding the abs.
The front wheel is spinning 6% faster. It’s something to consider.
The abs seems rather granular looking more for lock up to release rather than a subtle speed difference that would require more readings per second.
I base this on the small patches of rubber marks on the ground when braking hard enough to activate the abs.
Anyhow, the wheel has 6% less leverage over the brakes. That translates to about that much less effort at the brake lever to achieve the same braking.
Stainless lines give excellent modulation by way of a more direct connection between the hand and the calipers.
Why did I do this?
I was chasing a Miata up a twistie valley road that crosses the Back of the Dragon and with suspension upgrades, DMR front cartridges Penske shock, the bike felt greatly improved yet still ponderous beyond the simple explanation of being a heavy bike.
The geometry is not that much different than a Blackbird.
The 17” front wheel makes a huge difference.
It is 5.5 pounds lighter and with the half inch shorter radius the gyroscopic inertia is greatly reduced.
Hard mounting the handlebars to the triple clamp properly connects them to the front wheel for a precision feel.
The 1/2” shorter radius and the Penske shock extended just enough for the axle to clear the muffler and the result is a bike that changes direction very easily. It will pretty much stay in the turn until input otherwise is applied.
At the same time I moved up to premium suspension telling Traxxion to give me the best handling possible across twistie Appalachian roads in various conditions using AK20 cartridges and the Penske double clicker, I am willing to sacrifice comfort.
It handles great and 500 mile days are fine.
My other ST is set up for very comfortable 500+ mile days.
The most fun description of the bike was willsmotorcycle after riding PA route 666, saying,
“Dude, this isn’t an ST1300”
