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Brake disk switch
- Qdude
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Is it possible to switch out the solid brake disks for ones that are ventilated (gots holes?).
Seems that the ventilated ones would be more effective?
Has anyone ever done this?
77 KZ 650 C1.
77 KZ 650 C1.
Crashed-Repaired, Pods, Kerker pipe, re-wired core bundle, lamp upgraded, homemade rectifier, solid state regulator , Dyna-s ignition, repainted, slightly modified, year-round commuter
Honda Metro 85 mpg Scooter. Dont laugh I will throw it at you
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- KZ250LTD
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- OnkelB
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77 KZ 650 B1, 82 GPz 1100 B2.
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- 650ed
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1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- OnkelB
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In addition to the diameter be sure to check the thickness of the disks. I know some models were different than others, but I don't know the details. Ed
The stock 650 rotors are 7 mm thick and have a 6 mm service limit, the Z1R rotors are 5 mm thick and have a 4.2 mm service limit. The difference in thickness didn´t present any problems when I did the swap though.
77 KZ 650 B1, 82 GPz 1100 B2.
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- Qdude
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The stock 650 rotors are 7 mm thick and have a 6 mm service limit, the Z1R rotors are 5 mm thick and have a 4.2 mm service limit. The difference in thickness didn´t present any problems when I did the swap though.
This is the front brake here, I have to be sure that it is safe. Catastrophic malfunction here could easily be fatal.
Does this bother anyone else? With the disk swap from stock 7-6 mil. to ZR1 5-4.2 mil.? That is a 30 % reduction in brake disk thickness.
Is it possible that the calipers are different as well? If they are different calipers there might be a chance that the caliper for the thicker disk would be out of its service limits with a thinner disk, i.e the 5-4.2 ZR1 disk as opposed to its original 7-6 stock disk.
Does anyone know how often the calipers were changed or upgraded?
How many different calipers exist for any given year on Kawasakis? Did they use the same caliper on a 400 as they did on a 1000?
Does the caliper from a ZR1 have the same/or similar tolerances as the one from the stock 77 650 C1?
If not, I would need/want to change the calipers out with the disks to have piece of mind.
What are the thoughts?
77 KZ 650 C1.
77 KZ 650 C1.
Crashed-Repaired, Pods, Kerker pipe, re-wired core bundle, lamp upgraded, homemade rectifier, solid state regulator , Dyna-s ignition, repainted, slightly modified, year-round commuter
Honda Metro 85 mpg Scooter. Dont laugh I will throw it at you
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- RonKZ650
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321,000 miles on KZ's that I can remember. Not going to see any more.
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- 650ed
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When I compare the 2 front calipers to the rear caliper, they look the same except for the mounting brackets. But here’s the surprise. The part numbers for the front and rear caliper pistons are different. So are the part numbers for the piston seal rings. Is it possible that the differences in these internal parts compensate for the differences in the thickness of the rotors? Maybe the pistons are different lengths? Or maybe the different part numbers are totally unrelated to the rotor thickness. Inquiring minds want to know. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- steell
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The front does 80-95% of the braking
KD9JUR
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- Patton
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Thinner dual disc helped reduce unsprung weight.
Front master cylinder was 14mm bore for single front disc and was enlarged to 5/8 inch for dual front discs.
Reportedly, continuing with the smaller 14mm master cylinder when converting to dual discs (instead of using larger 5/8 inch master cylinder) results in overly sensitive braking, especially in emergency panic stop situations where front wheel unexpectedly locks and causes loss of control and bike turning over.
Best of Luck with whatever is decided.
1973 Z1
KZ900 LTD
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- PLUMMEN
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Still recovering,some days are better than others.
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- Qdude
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It is an issue of the drilled disks being thinner than the solid disks.
Come to find out that the drilled disks wear more rapidly, are thinner and lighter, and should bolt right up if bolt patterns match as the pistons will compensate.
77 KZ 650 C1.
77 KZ 650 C1.
Crashed-Repaired, Pods, Kerker pipe, re-wired core bundle, lamp upgraded, homemade rectifier, solid state regulator , Dyna-s ignition, repainted, slightly modified, year-round commuter
Honda Metro 85 mpg Scooter. Dont laugh I will throw it at you
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