Mini Bike Rebuild

[solomon]

http://sacramento.craigslist.org/mcy/1338520888.html

Pickin up that mini bike tomorrow
Only payin 50 bux
guy says its got a 3.5 or 4hp engine

What should i do with it?

Paint?
Rebuild Engine?
Hone Cylinder?
New Rings?

 

[freakboy]

Paint and run it till it dies why spend money on a rehone and rings. all i would do is clean it up and get it to run.

 

[EagleTalons]

What was it? I want pictures!

 

[solomon]

haha wow the ******* said it was mine and just sold it, what a an ***. Anywho just got a 5hp engine with a 1" shaft, Seems nice im gonna rebuild the carb and throw it on my go kart. I have 150 to put into what should i do

 

[EagleTalons]

What kind of engine is it? I'd do rings and gaskets for starters.

 

[solomon]

BRIGGS AND STRATTON 1984 CAME off a wood chipper, i took off the head and the valves were black (running rich?). Anywho there are cross hatches on the cylinder walls so IT was honed. And new rings i guess. good compression. installed a new head gasket and reassembled engine.It wont start unless gas is poured in carb so i assume it needs a rebuild
Although i fully dismantled it and it was perfectly clean and the diaphram was like new
I took some pics so i will upload in a minute

 

[EagleTalons]

Is it an I/C model?

 

[solomon]

 

[solomon]

I have no idea, but im mad at the shaft size clutches r expensive. I will be removing governor and adding clutch. My budget is 150 so figure 70 for a clutch and 5 for the gasket.

 

[EagleTalons]

Did you notice a sleeve when you were looking at the piston and cylinder? Also did you properly torque the head down?

That is one big shaft, haha! I'd try MFG supply first for a clutch. They generally have cheaper items. Will you be changing the rod when you take out the governor? If you are taking out the governor I'd put a Mikuni 22vm on it. Lots of power gain and they have many tuneable points on them.

 

[solomon]

i didnt pay attention if there was a sleeve but i think thier was. I do have a spare 3/4" crankshaft and i was thinking maybe i could swap them out? And just put in a different oil seal or would i need the whole side cover too? Where can i get one of those carbs? i didnt torque down the bolts i dont have those tools i have always just used a ratchet until they are tight. I am thinking about changing the rod, but only if i can swap the crank shafts.

 

[EagleTalons]

You'd need a new side cover. I'd begin checking Ebay. The Briggs Raptor has many parts that will drop right into 5hp engines.

I got my Mikuni on Ebay for 30 dollars. Runs great!

Also, it is important that each bolt be the same pressure or else it may cause the head to warp or the head gasket to fail.

I have a raptor rod in my engine. Fairly easy to install.

 

[solomon]

Thanks Eagle Talons, I do believe i have some spare sid covers so i'll check that out in a minute. I am thinking about installing a new rod but idk yet. I cant find that carb on ebay. And will it bolt right up? or am i gonna have to weld up an adapter.
I am thinking i will do this

-Remove Governor
-Pull Flywheel
-Change Crank Shaft
-New Flywheel Key
-different Side cover with new oil seals
-Lap Valves

I think all that should do it.

 

[EagleTalons]

I ordered a billet adapter so the surfaces would be true. It was only $19 and it came with a pulse fitting.