Xs750 896cc engine rebuild and chop!

Yeah, me too! My main worry is that the cylinder volume is too small for the calipers, and that the meathook lever has too short throw..
Hopefully i can test the rig this weekend, if all goes according to my wicked scheme!
 
what size is that master cylinder? usually it's marked on the side....if it's a 12mm it's good for one side....14mm MIGHT work for both...I forget what the stock front master cylinder is.
 
It only says 1/2, which i guess is half inch, but why would the japanese use inch? Stock master cylinder says 11/16, which i kinda doubt is an inch measure. Oh well, if this doesn't work I'll just ditch one front disc and caliper i guess.. or slaughter the stock master cyl and rework it completely to fit.. :D
 
Step 0: throw that rear M/C away unless you have calculated all the forces, leverage and friction etc in that cable operated rear M/C

Step 1: measure the pistons in the calipers you intend to use

Step 2: waltz on over to Vintage Brake and check out the chart to decide what master cylinder you need

Step 3: buy the appropriate size master cylinder

Who needs brakes. They just slow you down.....

Seriously though, play safe and fit a low mileage regular front M/C and stay alive.
 
Oh well i fucked up at step 0 already since im not an engineer and thus unable to calculate anything! :D
Anyhow i already have the boring fucking ugly stock unit lying around to put on there if this wont work out, which I'll probably notice quite soon..
Maybe even before I'm handed the darwin award.
On a more serious note, dont worry about my safety, i don't! ;)
 
Oh. I just realised.. im building a chopper.
Most of them dont even have front brakes.
I guess that means it's all good!
 
The stock front master on this bike isn't even a great gauge. They sucked also. All of this talk about MC sizes is making me think about mine again. I bought a smaller MC for the front which probably won't work now!
 
No, treitz, nothing ever works if you cant exactly calculate all the factors! :D
Thats why engineers dont build a lot of bikes i guess, it would be suicide to ride anything but completely stock..
Hell, my first bike was a rigid triumph chop with drums. 12" stretch and horrible geometry, and a violently tuned engine, ran like hell..
According to the play it safers my head would have exploded just by sitting on that thing, still here i am. Never died, had lots of fun, really miss that bike..
 
Actually looked at that vintage brake chart. 1/2" is gonna work fine, and when i reach the golden state of No flex - Full power, there will be peace in the valley once more. Only disturbed by the haunting wail of a triple nearing the 10k rpm rev limit.
 

Since welding is what i do best i weld alot of shit together and hope that shit works!
Electrolyte polished this little gem and it turned out sweet! All thats left to do now is notch the lever for the wire nipple and hook this sucker up!
 
Not really, been busy with other stuff, like rebuilding my old german 2stroker.. and buying a piece of land!
Got to grinding the tank today after work though, only some hours of wet sanding and polishing to go before i can start patination of the thing!
 
Here she is. A familiar view for me by now..
 

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datadavid said:
It only says 1/2, which i guess is half inch, but why would the japanese use inch? Stock master cylinder says 11/16, which i kinda doubt is an inch measure. Oh well, if this doesn't work I'll just ditch one front disc and caliper i guess.. or slaughter the stock master cyl and rework it completely to fit.. :D

Because (funnily enough) they actually do. I'm running the same brakes on my TR1 and in connection with braided brake hose a 14mm m/c turned out as the weapon of choice. Everything smaller, was too soft. That said, considering the fact that you'll loose a bit of force due to friction, I would go down to a 13mm m/c or a 1/2" anyway. Then again, you can always increase the length of the lever to increase the amount of force transmitted.

Cheers,
Greg

P.S.: ... that's one sick build.
 
der_nanno said:
Because (funnily enough) they actually do. I'm running the same brakes on my TR1 and in connection with braided brake hose a 14mm m/c turned out as the weapon of choice. Everything smaller, was too soft. That said, considering the fact that you'll loose a bit of force due to friction, I would go down to a 13mm m/c or a 1/2" anyway. Then again, you can always increase the length of the lever to increase the amount of force transmitted.

Cheers,
Greg

P.S.: ... that's one sick build.
I was kind of thinking for a second or two about lever ratio versus stroke length.. really not an engineer so i go by guesstimations! All thats needed to try this shit out now is the braided lines i ordered last week, a double banjo coupling, and drilling out the handlebar to accomodate the indian brass meathooks.
Testing dubious shit is interesting!
 
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