Spare_Parts
Well-Known Member
Thought I would share some info on the Boygofast 47mm steel sleeve cylinder. First off it is a steel sleeve. Did a super scientific test on it, touched it with a flap wheel and it threw yellow sparks. Red would be iron. Took some pictures, port mapped it and measured the height which is 70.6mm. The thing that stands out the most to me is the tapered transfer ports. It is not just the sleeve, the casting have the same shape. Next oddity is the intake port. It is a different shape than the casting. The sleeve hangs down past the top off the casting about 1mm. The "V" at the bottom is just random. The exhaust port seems close to the casting. This casting has open transfers with bridge and the exhaust port is also bridged. The transfers are no longer open because of the sleeve. Non of the bridging serves a purpose any longer so it should be removed. We are currently searching for chrome faced rings https://motoredbikes.com/threads/47mm-steel-sleeve-cylinder-ring-help.54285/
I'll keep this thread updated with any new info. I have some ideas to keep the sleeve from dropping or rotating.
Post 47 for updated ring info.
Ring set update!
https://motoredbikes.com/threads/boygofast-47mm-sleeved-cylinder-info.54304/page-6#post-480567
Picture time!!
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I'll keep this thread updated with any new info. I have some ideas to keep the sleeve from dropping or rotating.
Post 47 for updated ring info.
Ring set update!
https://motoredbikes.com/threads/boygofast-47mm-sleeved-cylinder-info.54304/page-6#post-480567
Picture time!!
View media item 61682
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View media item 61674
View media item 61678
View media item 61701
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