I've seen some strange and expensive contraptions for brake bleeding on bikes & cars, but I've had good success by using a cheap 60ml hospital style syringe with a length of clear pvc tubing fitted to the syringe body and the other end obviously connected to the brake bleeder nipple.
The syringe will give plenty of suction, and for the small volumes that we are dealing with on our bikes the capacity is plenty good enough. i.e. fit hose, crack nipple, pull syringe handle, draw fluid, bleed, keep an eye on the reservoir level, close nipple & you're done. This tool makes bleeding an easy one man job. The syringe also comes in handy for when the reservoir is a little over filled. After use just cycle some water through it to help preserve the plunger rubber from brake fluid contamination.
One more tip on this device; Make sure to drill a small hole in the side of the syringe body close to the top, near the limit its extension (i.e. the 55ml point) and then fit a largish blunted PK screw into the syringe body so that the plunger can not be completely pulled out of the body by accident during bleeding. Last thing you need is brake fluid all over your paintwork. Cheers guys.
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