1978 1T5 Yamaha XS750 SuperSport - repair, rebuild and fun log.
- Thread starter eMCZe
- Start date
eMCZe
New Member
Back to brake calipers...
after 20 years of use "serie oro" is not quite oro. The gold anodizing is dirty and scratched, and the calipers are covered in brake pad dust.
all sets goes into ultrasonic cleaner with an alkaline solution. After anodize stripping I have clean aluminium.
I did this with the calipers fully assembled because I didn't want to expose the piston bores and seal areas to chemical agents.
I still don't know whether to go back to gold anodizing or use powder coating in gold or another color.
The brake calipers were split
pistons are in excellent condition, and the black PTFE coating is free of scratches.
I ordered a pistons seal kit and few 6,8mm x 1,9mm EPDM o-rings for assembling both halves into a one piece.
here XS750 vs 900SS
I hope you aren't tired of my photos yet.
after 20 years of use "serie oro" is not quite oro. The gold anodizing is dirty and scratched, and the calipers are covered in brake pad dust.
all sets goes into ultrasonic cleaner with an alkaline solution. After anodize stripping I have clean aluminium.
I did this with the calipers fully assembled because I didn't want to expose the piston bores and seal areas to chemical agents.
I still don't know whether to go back to gold anodizing or use powder coating in gold or another color.
The brake calipers were split
pistons are in excellent condition, and the black PTFE coating is free of scratches.
I ordered a pistons seal kit and few 6,8mm x 1,9mm EPDM o-rings for assembling both halves into a one piece.
here XS750 vs 900SS
I hope you aren't tired of my photos yet.
eMCZe
New Member
I had little accident... completly crash my car on highway 
but today had time for Ducati susspension.
I bought from Ducati SuperSport 2001 and borrow one from Ducati Monster 900 2002 to compare and show you why choose SS.
First few fork measured datas:
Yamaha (1T5 from 78')
- Fork leg length (top to axle center) 790mm
- Fork pitch 185mm
- Inner fork tube diameter 36mm
- Outer fork tube diameter 48mm
- Axel diameter 17mm
- Travel 170mm
- Offset 45mm
Ducati Monster 900 2002
- Fork leg length (top to axle center) 695mm
- Fork pitch 205mm
- Inner fork tube diameter 43mm
- Outer fork tube diameter 50/54mm
- Axel diameter 25mm
- Travel 130mm
- Offset 30mm
Ducati 900 Super Sport 2001
- Fork leg length (top to axle center) 725mm
- Fork pitch 205mm
- Inner fork tube diameter 43mm
- Outer fork tube diameter 50/54mm
- Axel diameter 25mm
- Travel 120mm
- Offset 25mm
How does this affect the handling?
Serial Yamaha - trail and rake for Yamaha XS750 are 27 deg. and 114mm - This bike rides straight as an arrow, it’s super stable, and doesn't get upset by bumps or wind. The downside is that you have to muscle it into corners because the machine just loves going straight. Because of the long 170mm travel and a soft fork, the Yamaha dives hard under braking and squats when you hit the gas, which crazy changes the handling depending on the situation.
XS 750 with my baloon 4,5-18 rear and 4,0-19 front wheels - trail and rake are 27,5 deg. and 132mm - Yama rides like train... To restore the factory setup, the fork tubes need to be pushed up into the top triple tree.
XS with M900 USD - 24,2 deg and 123,5mm - the geometry is similar to the stock XS, bike tracks straight as an arrow and sometimes needs to be muscled into corners, but the stiffer fork, overall rigidity, and shorter travel provide stable handling and predictability under braking.
XS with 900 SuperSport fully regulated Showa USD - rake 25,4 deg with 137,5mm trail - The XS SS handles even heavier in corners than the stock 750 on baloon tires, riding like a Triumph Rocket and edging into Power Cruiser territory... but the big advantage is the fully adjustable Showa fork, with full control over preload, rebound, and compression.
However, there is a remedy: the difference in fork length between the M900 and 900SS stems from how the handlebars are mounted. The M900 fork ends flush with the top triple clamp (allowing clip-ons under the triple clamp), while the 900SS fork extends above it to accommodate clip-ons over the top triple clamp.
- 3cm lower and I have 24,15 deg. 126,8mm almost the same like M900 USD but with workout for me on corner.
- 3,5cm lower gives 23,95 deg. 124,1mm and it should play on corner like light street fighter and still will good straight.
It's not the end about fork.... to be continued.
but today had time for Ducati susspension.I bought from Ducati SuperSport 2001 and borrow one from Ducati Monster 900 2002 to compare and show you why choose SS.
First few fork measured datas:
Yamaha (1T5 from 78')
- Fork leg length (top to axle center) 790mm
- Fork pitch 185mm
- Inner fork tube diameter 36mm
- Outer fork tube diameter 48mm
- Axel diameter 17mm
- Travel 170mm
- Offset 45mm
Ducati Monster 900 2002
- Fork leg length (top to axle center) 695mm
- Fork pitch 205mm
- Inner fork tube diameter 43mm
- Outer fork tube diameter 50/54mm
- Axel diameter 25mm
- Travel 130mm
- Offset 30mm
Ducati 900 Super Sport 2001
- Fork leg length (top to axle center) 725mm
- Fork pitch 205mm
- Inner fork tube diameter 43mm
- Outer fork tube diameter 50/54mm
- Axel diameter 25mm
- Travel 120mm
- Offset 25mm
How does this affect the handling?
Serial Yamaha - trail and rake for Yamaha XS750 are 27 deg. and 114mm - This bike rides straight as an arrow, it’s super stable, and doesn't get upset by bumps or wind. The downside is that you have to muscle it into corners because the machine just loves going straight. Because of the long 170mm travel and a soft fork, the Yamaha dives hard under braking and squats when you hit the gas, which crazy changes the handling depending on the situation.
XS 750 with my baloon 4,5-18 rear and 4,0-19 front wheels - trail and rake are 27,5 deg. and 132mm - Yama rides like train... To restore the factory setup, the fork tubes need to be pushed up into the top triple tree.
XS with M900 USD - 24,2 deg and 123,5mm - the geometry is similar to the stock XS, bike tracks straight as an arrow and sometimes needs to be muscled into corners, but the stiffer fork, overall rigidity, and shorter travel provide stable handling and predictability under braking.
XS with 900 SuperSport fully regulated Showa USD - rake 25,4 deg with 137,5mm trail - The XS SS handles even heavier in corners than the stock 750 on baloon tires, riding like a Triumph Rocket and edging into Power Cruiser territory... but the big advantage is the fully adjustable Showa fork, with full control over preload, rebound, and compression.
However, there is a remedy: the difference in fork length between the M900 and 900SS stems from how the handlebars are mounted. The M900 fork ends flush with the top triple clamp (allowing clip-ons under the triple clamp), while the 900SS fork extends above it to accommodate clip-ons over the top triple clamp.
- 3cm lower and I have 24,15 deg. 126,8mm almost the same like M900 USD but with workout for me on corner.
- 3,5cm lower gives 23,95 deg. 124,1mm and it should play on corner like light street fighter and still will good straight.
It's not the end about fork.... to be continued.
eMCZe
New Member
I have another possibility, I can use old SS triple clamps. The same fork OD, the same 26mm stering axle but with 30mm offset. It should be better for stering, I orderd one more set
If you want use Ducati fork you need to know what you want, some parts has the same part numbers but are from not the same model. Down triple clamp number 342.3.014.1A from 2001 can be from Ducati Monster 900 but one is with thin stering axle and second with thick.
here is for 26 mm ID bearing
here is for 35mm
why it is important ?? because of Yamaha XS steering bearings.
top is 25 × 47 × 15 mm
down is 30 × 55 × 17 mm
Ducati has
for thin axle 26 x 52 x 15 - 2 pcs
for thick axle 35 x 55 x 14,5 - 2 pcs
I checked lenght of Ducati steering Axle and should be ok for Yamaha
so I only need to use new conversion bearings, but... only with thiner one.
on top I need to change from 25 x 47 x 15 to 26 x 47 x 15
on bottom I can use standard Yamaha bearings 30 x 55 x 17 with sleeve 26 x 30 on Ducati steering axle.
now I wait for this new parts and will try to marriage this.
If you want use Ducati fork you need to know what you want, some parts has the same part numbers but are from not the same model. Down triple clamp number 342.3.014.1A from 2001 can be from Ducati Monster 900 but one is with thin stering axle and second with thick.
here is for 26 mm ID bearing
here is for 35mm
why it is important ?? because of Yamaha XS steering bearings.
top is 25 × 47 × 15 mm
down is 30 × 55 × 17 mm
Ducati has
for thin axle 26 x 52 x 15 - 2 pcs
for thick axle 35 x 55 x 14,5 - 2 pcs
I checked lenght of Ducati steering Axle and should be ok for Yamaha
so I only need to use new conversion bearings, but... only with thiner one.
on top I need to change from 25 x 47 x 15 to 26 x 47 x 15
on bottom I can use standard Yamaha bearings 30 x 55 x 17 with sleeve 26 x 30 on Ducati steering axle.
now I wait for this new parts and will try to marriage this.
eMCZe
New Member
Good news... my spoked wheels are on the ship from Japan and will start long way to Europe. I bought triple clamps from Ducati with 30mm offset for my SS USD fork (in Japan too). My Brembo calipers goes to paint shop, probably will be gold as brake rotors. As you see, no post day by day but still work on bike.
eMCZe
New Member
Today I pick up package:
it's only triple clamps but now I can go further with Showa USD.
Here you can see offset diference:
I will use left one with bigger 30mm offset. All parts were cleaned and ready to conversion.
Do you remember this ??
so I bought set
KOYO SAC 2647-1 26x47x15 on top and KOYO HI-CAP 32006 JRRS 30x55x17 on bottom. On workshop I ordered sleeve 26x30.
and...
will be continued...
it's only triple clamps but now I can go further with Showa USD.
Here you can see offset diference:
I will use left one with bigger 30mm offset. All parts were cleaned and ready to conversion.
Do you remember this ??
so I bought set
KOYO SAC 2647-1 26x47x15 on top and KOYO HI-CAP 32006 JRRS 30x55x17 on bottom. On workshop I ordered sleeve 26x30.
and...
will be continued...
eMCZe
New Member
Yesterday I cleaned brake rotors and went to my friendly paintshop.
because after checked few shade of gold nothing was like I wanted, I decided to paint brake calipers and triple clamps to black. It will takes few days, so I started preparation to wheel conversion.
First I disassembly hub bearings and seals.
1) Bearings:
In Yamaha XS750 on front we have both side 6303Z - 17 x 47 x 14mm
so I need 47 mm OD (Yamaha hub) and 25 mm ID (Ducati axle). I need to choose between:
- standard Ducati bearings 6005-2RS 25 x 47 x 12 mm
or
- special bearings 62005-2RS
standard is cheap and I can buy it everythere, special is more expensive and hard to buy. The only thing I need to adjust after selecting the bearings is the outer sleeves - making them 2 mm longer or shorter.
2 Seals:
Yamaha has two different seal. from speedometer drive side 45 x 56 x 6 mm and from right side 28 x 47 x 7 mm, so I need use both Yamaha OD and ID depends on the thickness of the spacer sleeve. Ducati use 35 x 47 x 7 mm because of 35mm spacer OD.
Inside hub, between bearings is inner sleeve. The hub is hollow inside, which is why there is a narrower opening on one side for a centering collar. Without it, the sleeve would simply fall loosely inside.
Inner spacer has 68,5 mm
but after I measured everything I look at the photos of spoked hub and... both hub ID are the same without narrower opening for a centering collar.
so I need to wait for hub and measure inner spacer one more time
because after checked few shade of gold nothing was like I wanted, I decided to paint brake calipers and triple clamps to black. It will takes few days, so I started preparation to wheel conversion.
First I disassembly hub bearings and seals.
1) Bearings:
In Yamaha XS750 on front we have both side 6303Z - 17 x 47 x 14mm
so I need 47 mm OD (Yamaha hub) and 25 mm ID (Ducati axle). I need to choose between:
- standard Ducati bearings 6005-2RS 25 x 47 x 12 mm
or
- special bearings 62005-2RS
standard is cheap and I can buy it everythere, special is more expensive and hard to buy. The only thing I need to adjust after selecting the bearings is the outer sleeves - making them 2 mm longer or shorter.
2
Seals:Yamaha has two different seal. from speedometer drive side 45 x 56 x 6 mm and from right side 28 x 47 x 7 mm, so I need use both Yamaha OD and ID depends on the thickness of the spacer sleeve. Ducati use 35 x 47 x 7 mm because of 35mm spacer OD.
Inside hub, between bearings is inner sleeve. The hub is hollow inside, which is why there is a narrower opening on one side for a centering collar. Without it, the sleeve would simply fall loosely inside.
Inner spacer has 68,5 mm
but after I measured everything I look at the photos of spoked hub and... both hub ID are the same without narrower opening for a centering collar.
so I need to wait for hub and measure inner spacer one more time