Crashedkiwi
XS650 Enthusiast
Hi there all; Could someone kindly post or direct me to where I might find a template for drilling my front disc please?
After all, why not?
Cheers
After all, why not?
Cheers
I drilled 2 discs... 84 holes per disc... with a single 1/4" drill bit. No pilot holes, just marked with a center punch and drilled.Am curious how easily are these stainless discs drilled.
Cheers Jim; that looks perfect & a great job done also!Here ya go. https://www.xs650.com/threads/how-to-cross-drill-rotor-w-patterns.12671/
The pic links are broken but the PDF files still work. I used one of 'em to drill the rotors on my SG. Don't recall which but I do remember having to resize the drawings. The guy who made 'em put a convenient scale on there to help with that.
Also... if I recall correctly, he didn't include the outermost holes. Those need to be there to cover the entire swept area. It was pretty easy to add those in.
Here's where I did mine. https://www.xs650.com/threads/jims-1980-sg-miss-september.50545/post-604386
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As ever 5twins, sensational! Thanks for the insight and patterns! 3B!I started out years back on my 1st disc with a 7 hole swirl and 6 swirls .....
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This worked OK but I wanted more holes. I also didn't like the way the outer hole was so close to the edge of the disc. It's held up OK so far but I figured the disc may eventually crack out there. For my next disc, I acquired a 5mm thick SR500 one. I laid the above pattern out on it twice to get more holes, and I made them smaller (3/16"), but with only 7 holes in a swirl, the smaller hole size didn't cover the whole swept area. I compensated by making the first and last hole in the swirls larger. I alternated them, making the 1st hole larger in one, the last hole larger in the next .....
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But really, I needed a new pattern, so I drew one up. This one uses 15 swirls of 8 holes each and was set up to use 3/16" or 5mm holes .....
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But next came a new dilemma, lol. After researching the ideal hole size, I found that you get the biggest benefit (most additional surface area created for better cooling) if you use holes the same size as the disc is thick. So, while my new pattern was perfect for 5mm thick discs, it wasn't so good for 7mm thick ones like the stock 650 has. Now, I couldn't enlarge the outer hole much as it was already pretty close to the edge, and the inner hole was already part way off the pad's swept area, so I didn't see the point of enlarging it. So, I settled on just enlarging the 6 middle holes in each swirl. This worked out well and gained me lots more surface area, very close to what all 7mm holes would give .....
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I've attached a PDF of my pattern if anyone would like it.
( on the fence about twin discs; I've the potential to do this but I'm having an asthetic debate with myself on this)
You have to set a priority as to what is more important to you. That nice balanced two brake appearance comes at the expense of almost 10 lbs of unsprung weight. For some, that’s meaningless. For others, it’s a deal breaker.Nice! Hmm.... My build is a custom cafe look so I'll go imagine this against my mental image of the bike.