Multiple BbK break in theories

[toquima99]

Hi everyone,
Just completed Tank classic BBK 72cc. Wanted to get some feedback on break in. I've looked up a dizzying array of theories from "ride it like you stole it" to "don't go far past half throttle for 300 miles."
90gtvert says take it easy for a little while but running it like you normally do does not seem to hurt since he has done that many times with no problem. I trust him since I followed his BBK install post.
I put two stoke oil on the cylinder and cam like he said during install and it started and ran great.
Here's my setup:
Japanese carb for 49cc (manufacturer says it has a few mm larger Venturi than standard 49cc carb)
Put in 35 idle jet and 85 main jet with stock air box because I was concerned with too low vacuum off idle with the pod filter.

With the 72cc, will it make plenty of vacuum so I can ditch the stock air box and put in a free flow pod air filter? Will it run too rich with the stock air box?

Put on a performance exhaust header with a straight through perf muffler.
My goal was mostly stock (except engine internals) with improved real world rideability, I don't want burnouts or wheelie's, just solid reliable performance.

Should I keep the 35,85 carb setup and go with a pod filter? Or go with an 40 idle jet and pod filter? Or keep it just like it is.

Went for a 5 mile ride after install, seemed to run fine, good response, nice smooth power, very much improved over 49cc.
Let me know what you think.
Thanks!

[90GTVert]

I actually always run the heck out of them as soon as I get them going. I have broke them in easy before, but I don't see a major difference either way, so I might as well get to the good part. lol

It should be OK with a pod filter, but you're probably gonna need to upjet the main again. Might need a 38 pilot.

[mccanic]

i've always done heat cycles, from ride for 15mins then let it fully cool off then 30min then back to 15mins and so on till the gas tank is fully empty. when riding i dont hold it wo for more then 1 min. idk thats just what i grow up doing. hope it helps
my last bbk i just beat that hell out of it and that didn't work.... im blaming the cylinder lol motoforce cheapo haha

[90GTVert]

That reminds me... for anything running multiple base gaskets for whatever reason, getting the engine hot and later re-torqueing can be important. It doesn't matter so much with some gasket materials, others may compress a good bit. I had one recently with a thin sealing surface at the base that compressed so much on the first ride that I lost a lot of compression and couldn't refire the engine once it was shut off. It's quite uncommon to be that severe, but it never hurts to check.

[toquima99]

Thanks for the response, I'm still learning and you guys have been a great help.
I was just happy it started up and then ran fine on the road.

[2strokd]

Thats what counts the most in the long run... All the rest leading to that are just details. The better the details are planned and worked, the better the outcome. Sounds you did well enough with the details! Congrats!!!!

[tango]

I remember when I rebuilt the engine in my 1987 Hyundai Excel. The mechanic said not to go over 50mph for the first 300 miles. I followed that slavishly and shifted early, all the rest of it. That engine felt tight as a drum all the way to 300 miles. As I passed 350 I just said screw this shit and GUNNED it for 20 miles. After that it felt proper. Have a look at this site I found a while back. The guy says to drive them hard and he makes a lot of sense.

www.mototuneusa.com/break_in_secrets.htm