Hyper Crusier/ Zeda case reed build

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This build is kinda odd for me. I typically don't start any project with all new parts. Most of my stuff is but with old junk and some new stuff. That's how I picked the screen name.

My last bike (first MB) was fun but had all kinds of problems with the Seeutek. Bearings went, then it broke a ring, next was wrist pin bearing failure that cracked the piston dome and then the final catastrophic lean the took out the entire top end which was caused by a broken carb. The bike itself also had issues with the derailleurs and brakes due to riding in the winter. Needed a repaint as well. Fvck that. This time I'm starting new.

So....
I decided this bike was going to be a single speed cruiser with disc brakes to solve my biggest issues with the bike itself. Hard combo to find. Found the Hyper at Wallmart by chance and it was cheap, real cheap. Comes with coaster brakes. No big deal, I like building rims and this way I can have exactly what I want. Besides the rims The only other things that needed to be changed are the pedals and handle bars. The bars are like 3' wide WTF. With my BMX background platform pedals is all I'll ride. Both of those issues have been taken care of.

For the engine I picked Zeda because a lot of people seem happy with them. Knew I wanted a reed for the power curve and I ended up going overboard and ordering the Zeda 80 case reed and a MZ65 pipe at the same time. Ship date is between 3/14 and 3/21.

Parts acquired so far:
  • Single speed disc hubs
  • Disc rotors and calipers
  • KMC Z510 chain
  • ODI grips
  • Dual brake lever
  • Matching clutch lever
  • Narrow 10 sprocket from BMW
  • CNC throttle
Parts to be ordered:
  • Huffy Davidson Lightning Strike CDI
  • Disc Drive sprocket adapter and 410 36t sprocket from MBRebel
  • OZ super magneto
  • 12g spokes and nipples
  • Double wall rims
  • Lighting

 
The transfer window area on this cylinder is much smaller than the open walled area of the first one and this will increase the velocity at opening,combined with the booster port will lower it closer to what the wall less one was at since it can only really drop so much,raising the transfers just a mm above the boster would bring the pressure back up for a faster delivery of the charge but reduce the blow down duration,this still leaves plenty of duration thought and leaves scavaging time in the boost port and final duration of transfers,mostly though it will be the pipe tunning that's going to make or break this setup type imo.
 
that no transfer wall cylinder i was running one similar recently got me over 50mph but i couldnnt get it to idle right but it could have just been an air leak as well tho but it was beast
 
@Street Ryderz
I have just started reading Jennings book and think it's time to step up and do my own cylinders. I'll get some measurements and post them when I get a chance.
that no transfer wall cylinder i was running one similar recently got me over 50mph but i couldnnt get it to idle right but it could have just been an air leak as well tho but it was beast
Mine idles great and got it to 47.3 mph. Part of the reason I got so pissed when I saw the new one.

My current setup has on base gasket and a 0.8mm head gasket. Picked up two base gaskets, 0.4 and 0.6 head gaskets. Also have a few different thicknesses of paperboard to make so base gaskets to fine tune squish.
 
Sexyyy makes me wanna lap my gold head and get it on something ive got two messed up bottom ends i wanna finish tearing apart to assess the salvageable parts and start putting together this new crankcase i bought from mz awhile back its only got crank bearings in it and cylinder studs lol but i know their garbage bearings so figuring out how to get those in and out so i can put high quality ones instead is on my list plus getting the clutch side big slotted bolt out is being a s.o.b. i think i need to heat it up not sure thats the only one holding them together thats stopping me
 
Sexyyy makes me wanna lap my gold head and get it on something ive got two messed up bottom ends i wanna finish tearing apart to assess the salvageable parts and start putting together this new crankcase i bought from mz awhile back its only got crank bearings in it and cylinder studs lol but i know their garbage bearings so figuring out how to get those in and out so i can put high quality ones instead is on my list plus getting the clutch side big slotted bolt out is being a s.o.b. i think i need to heat it up not sure thats the only one holding them together thats stopping me
I've had some where that bolt was epoxied in or jb welded why i don't know but had to drill into the face and use an extractor to remove it!
 
The chrome was chipping away in the cylinder.

I noticed a big difference in the widths of the 2 exhaust ports. Old is 31mm wide and new is 25mm. The third transfers also are different. New is smaller but didn't measure. Didn't touch anything which is hard for me lol. Squish measured at 0.83mm. Would like it a little closer so I might sand down the cylinder. Forgot to check cylinder heights. Hell, I forgot to measure most of it. Engine is back together now and just messing with dumb little stuff because it's raining.



 
Got the top end painted and installed. Had to lean out the slow jet and needle but left it a little rich. The main jet seems fine. Pulls a lot different now. Doesn't feel like it is pulling as hard on the bottom end but feels like it accelerates quicker. I know the doesn't make any sense lol. Think it is because most of the vibration went away. Guess I was completely wrong about the cylinder and will go back and edit my posts.

Installed the new cranks and sprocket today. Went from a 44t to 42t and had already changed the rear from 16t to 18t. Much nicer pulling away from a stop.

Also ordered everything to convert ther rear hub from loose ball and 3/8 axle to sealed bearing 1/2". I have bent 2 axles now because it has 16mm worth of spacers on it. If this doesn't work think I'll get the Ghetto bike hub.


 
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Looks great but MAN I miss that in frame tank. It really brought everything together.

Are those cranks longer than the stock ones? I know on my Hyper the pedals would hit pretty early during a turn if you tried to pedal out of it at low speed.
 
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