The Yellow Jacket build thread

datz510

Member
I figured I should make a thread for my yellow Whizzer that I traded my Rotten Orange to lennyharp for. The bike is gonna be one mean Whizzer, so i'm calling it the Yellow Jacket!

Here is the Whizzer and I at the Death Race 2009 event this weekend:
whizzer006.jpg


Couple more pics of the bike:
whizzer002.jpg

whizzer003.jpg


This thread is going to cover the modifications I'll be making to the bike. For now, I'll start small and then work my way up to something wild in the next few months.
 
Datz, A Fine Machine For Sure. In 1951 I Bought A Brand New Whizzer "rear Wheel Pulley ". I Think We Paid $3.25. That Seems High For That Time. I Wonder If Anybody Has An Old Price List. Ron
 
Can You Start The Motor When On That Center Stand? I Think The Old Whizzers Had That Heavy Duty Unit On The Rear Axle And A Latch On The Rear Tip Of The Fender, Maybe It Was On My 1936 Harley. RON
 
Yep, I use the center stand all the time for starting up the bike. It is more than adequate to hold the bike and myself.

Yesterday, I got the majority of the issues sorted on the Whizzer. The low rpm power issue turned out to be caused by the intake valve having over 0.020" of lash in it. I set it to 0.006" and she runs great now! It gained even more low end torque when I reinstalled the baffle in the exhaust, so I ordered up a spare one so I could experiment with modifying the baffle length.

I ordered a slew of parts for the Whizzer for the first round of modifications. I'll be posting up as I get them installed. The bike is going to be really retro. :)
 
was wondering how long it would take till ya just had to tinker :)
this is gonna be a fun thread !!!
 
thats a very nice looking bike, and about as close to a moped as any I have seen here. It is impressive to be sure, how do you like the belt drive vs chain drive. My guess it would be quieter and less greasy maybe ?
 
Love the belt
drive! It is very quiet and clean. I do miss the positive engagement of chain drive though.

The Whizzer is definitely closer to a moped. It is terrible to pedal for more than 100ft or so.

Legally here in AZ, I had to register it as a motorcycle due to the large displacement.
 
haha yea pedaling these MB can be hazardous to ones health for sure , but any way I look at it your MB is simply one beautiful piece of work. Makes me really want to put some effort in to my next build .

thx for posting these pics, they have given me inspiration for real
 
Just for the record, aside from getting it running right, I really havent done much to this bike.. I didnt build it. This is a 2008 Whizzer that lennyharp bought and then I traded him my Rotten Orange build for this bike.
 
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very cool - does it have an auto clutch? when you re-did the valve lash, did you change the lifters? whats that filter thing with the tube that goes down the back of the bike?

i just got done doing a half ass overhaul of my whizzer, new head gasket, intake manifold, mushroom lifters, advancing the cam and setting a new lash.

just a few conversations with mike and quinten cleared up a lot of questions i had!
 
Yep, this one has an auto clutch. The filter thing I believe is a PCV valve.

I didnt change the lifters out as they had already been worked over with the addition of Quenton's top-end work.
 
Tonight I fitted the new Brooks saddle. Looks GREAT on the bike and is comfy.

Tommorrow, I'll take some photos. I'll also be working on modifying a Monark frontend to beef it up for Whizzer duty. :) This bike is going to be really cool when its done.
 
Lifters should be good as they showed no signs of wear after 600 miles of riding. We need to go riding soon, Say Tortilla Flat and beyond.
 
Tortilla flat would be great, as thats a relatively slow road anyway and we can reach it using surface streets from Mesa.
 
Here are some new pics of the Whizzer. Did a bunch of work on it. Fitted a Brooks B67 seat, laidback seatpost, small seat bag, and a cool vintage looking rear rack.

whizzer04.jpg

whizzer05.jpg

Also rerouted the PCV valve and tubing to hide it a little better. Looks a lot cleaner now:
whizzer06.jpg
 
The bike is looking great. I rode the Orange to work tonight and appreciate your quality work. I still am anxious about the free wheel at the crank. So far it is good, but you have nothing to do about that. I think maybe we can go out to the tortilla flat next week maybe.
 
I'd really like to get the new carb on the Whizzer before any major rides. I've found that the engine is leaking oil from most of the gaskets, so its gonna need a complete teardown and reassembly soon with new gaskets and sealant..

I had some issues with it today after about a 30 minute ride. It started losing power felt like the carb was possibly overheating... i checked the engine temp and it appeared to be OK.. around 430F
 
Well, I think I have the problem narrowed down to being electrical... ignition specifically.

I pulled the plug and found the plug gap to be set at .015" and the plug was terribly carbon fouled. I cleaned the plug and then reset the gap to .024" and now the bike barely runs. Spark is very very weak. So, I gotta find a wiring diagram so i can start tracing this thing out.
 
That is what I was complaining about before. It just takes a more persistent and knowledgeable mechanic to get to the bottom of it. So far the Rotten Orange is not so rotten.
 
Glad to hear the orange is working well. :) I'll get the whizzer figured out, its just gonna take some time.

I managed to get ahold of a wiring diagram for the NE5, so now I have a starting point to diagnose the issue at hand. I think i'll start by pulling the wiring harness out and checking it out thoroughly. Will probably also replace the connectors on it with better ones if they look flaky.

Here is a link to the wiring diagram if anyone else is in the same predicament as me:
http://www.piratepathy.com/WhizzerWiring.pdf
 
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