Just given two briggs flatheads What now?

leoofc

Member
I was just given a minibike and two briggs flathead motors. One motor is an IC industrial that says 5hp and has a dropped down large carb unfamiliar to me.I am used to the pulsajet carb on my gokart. The other has a pulsejet carb but is shorter and has the adjusting needle at the base of the carb and is different from the standard raptor type carb. Are these motors usable for the minibike and which would be better? Any thoughts would be appreciated.
 

flattop1

Dawg 89
The dropped down carb has a float bowel . The engine itself is fine the intake system is somewhat restrictive .
The other carb sounds like a fun power style with the adjusting needle being an air screw not a fuel adjustment . The jet is at the bottom of the stem in The tank .
Either one should work depending on your needs .
 

Lkerley

Member
I run Flatheads on all the mini bikes I have they work great.Yours being stock should bolt up and work.You do most off the time have trouble adding an aftermarket air filter though clearance issues.I run a 35mm 90 degree filter to clear on a raptor carb though.If you decide to upgrade put you a raptor carb and tank on the fun power motor it will help it out.
 

leoofc

Member
Thanks for the quick replys.I sure came to the right place for answers. I take it that all these intakes are interchangeable with the proper tank with the raptor style being the best for a minibike. I already stripped all the governor stuff off the fun motor and was wondering how to hook throttle linkage. Now I think I will change to raptor style with the ready made linkage. Thanks again.
 

Lkerley

Member
Yes.The raptor carb part#555129 tank #555192..The linkage on eBay is around 8.00.With the governor deleted be real careful and not over rev it or the rod will go.I think max is 4800 rpm's on the stock rod."that's not wrote in stone"
Check "personal items" for sale on this site to find your parts..
 

flattop1

Dawg 89
Filter adapter is different on the fun power as well it vents through there .
Something about the throttle shaft seems differnt also though its been years so im likely wrong .
Raptor carb might be smaller diameter too .
 
Last edited:

Lkerley

Member
No.Your right you'll have relocate your breather hose if you go to a raptor carb.You can use part#bvtka to help you run it to a vent filter like part# up-121 gopowersports sells small vent filters part#38-9139.I run mine to a catch can.
 
Last edited:
Yes.The raptor carb part#555129 tank #555192..The linkage on eBay is around 8.00.With the governor deleted be real careful and not over rev it or the rod will go.I think max is 4800 rpm's on the stock rod."that's not wrote in stone"
Check "personal items" for sale on this site to find your parts..
I found out quick that the weak link was a std rod with the steel bolt on dipper...bad news. I myself have many sq ft of flathead parts single and duel bearing blocks , welded and shaped heads and boxes of nos parts and complete engines so if anybody wants parts pm me .
 
Top