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Bubble Volume and Brake Hose diameter!

721 Views 2 Replies 3 Participants Last post by  qkenuf4u
So I was bleeding my dirt bike brakes today and was amazed how easy it was to get the air out of the lines. Motorcycle brakes are very similar to Shimano and how they are bled. But I noticed that the larger diameter brake hoses and larger diameter bleed hoses allowed the air bubbles to freely move through the system. Um duh right?

So the smaller lines and fittings on mtb brakes make it harder for the air to move out of the system from what I experienced.
Kind of a catch 22, Smaller, lighter, harder to bleed.

Anybody else ever notice this?
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Interesting food for thought

I haven't bled anything besides mtb brakes so I haven't noticed that difference, but I was surprised to find how small an air bubble can ruin the feel of my Shimano brakes. The smaller piston, smaller fluid volume, etc seem to make it more intolerant than I imagine a larger system would be of very small bubbles.
hmmm havent bled my m755's yet but i will soon.... im a MOTORCYCLE TECH so i use a MITY-VAC for all brake bleeds.. im curious if it will make a difference ?
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