Z50 A1 160cc Cafe Racer

[69ST]

It turned out very well. Going to the final two-tone color scheme really transformed the overall look. IMO, the longer-than-stock fork legs look good, as does your rear brake setup. That beefy brake rod & spherical end appear "all business". It's up to you as to whether, or not, the pedal assembly should be visually refined. If you're like most dedicated gearheads, you probably won't be able to resist; custom machines are never truly finished, only photographed at various points in a prolonged state of evolution. :4:

Just a thought on custom intake fabrication...source a short piece of mandrel-bent stainless tubing with an ID that's either the same as the intake port, or 2mm smaller, then bore the flange hole slightly larger than the tube OD and bevel the engine side. That will allow you to adjust the carb angle, once the height is where you want it. Weld from the inside and you'll get a seamlessly finished piece. I'm not suggesting that this is necessary, or that there's anything wrong with your intake...it's only a thought that your post brought to mind.

 

[judasbrutus]

You are 100% on point with the intake and this was my original plan but a few trips to suppliers came up without results for the correct size. Being impatient I did the hard (less than ideal) way. At some point I will go the proper rout.

What a sad day if a "project" ever finished.

 

[69ST]

Wish I could recall where mine came from. The flanges & 28mm mandrel-bent pipe (all 3-series stainless) were sourced from an outfit that supplied dairy processing equipment, I can't remember which one. Maybe this will get you pointed in the right direction.

Considering that you're not using this bike in open competition, I reckon that a tiny amount of lost power is a non-issue, no guarantee that this is happening. In fact, the rough interior walls could be working in your favor by preventing a smooth boundary layer of airflow. Smooth intake walls oftentimes cause poor/uneven atomization. I was thinking in terms of aesthetics and if the thought of a detail that, as yet, isn't as good as you would like it to be keeps gnawing at you.

 

[judasbrutus]

At some point I’d love to buy a downdraft pumper carb to eliminate as much intake tract as possible. Also I used steel epoxy on the interior walls and buffed it smooth to help with the venturi turbulence. I am however a strong fan of stainless wherever possible. I also have a finned insert (used on scooters) that helps mix gas/fuel. It seems to help at mid range. I didn’t think it would but was surprised.

Also my intake and carb are 26mm to match the intake port.

Clearly you know what you're talking about and thanks for the help.

 

[P.C.]

had a YX140 and smoothed the inside of the intake and it gave me better low to mid range.the bike lifted the front end alot easier and earlier when i nailed the gas.