Transfer Port Modification- Pictures and results here.

[Brains]

G'day europorsche, yes my motors are available for purchase, I have been doing so for quite some time now, & to answer your question Technocyclist we change all the bearings with quality made bearings which are manufactured in Australia.

The bearings which are used in the clutch housing are totally sealed internal & external, the reason why I do this is to ensure debris is kept out of the ball baearing race, but the bearings which are used in the crank housing are totally sealed externally to crank shaft & housing, the internal race is open, for the reason of ensuring they are lubricated with oil whilst motor is in operation. The conrod is relifed at big & small end to allow greater points of area for oil to enter the bearing race as well.

Cheers All
Brains

 

[Creative Engineering]

I have an Austrailian counterpart...Awesome!

Actually there are a lot of guys with shops and I suspect that the custom parts market for these bikes wil grow rapidly.

Brains...Is that a factory crank that you show in your photos? All of the ones I've got have weights that are attached with M6 machine screws.

Jim

 

[europorsche914]

I have an Austrailian counterpart...Awesome!

Actually the are a lot of guys with shops and I suspect that the custom parts market fro these bikes wil grow rapidly.

Brains...Is that a factory crank that you show in your photos? All of the ones I've got have weights that are attached with M6 machine screws.

Jim

my original BGF engine and replacement crank both were 3 part cranks (2 counterweights and pin) no m6 screws here. Mine appears identical to the one in the picture except my pin is hollow. -Justin

 

[Creative Engineering]

As far as i know Chris Hill and Jim @ Creative Engineering are the only ones improving and selling these engines. Chris Hill replaces the bearings and rounds the edges of the ports (from his website). Jim will be producing engines on a small scale and the details will be found in a thread that he will post within the next few days. I dont know if brains is planning on selling his machined parts but he obviously has the tools to get it done -Justin

I'm working on it guys...I've been taking a lot of photos, and writing descriptions. I've also put together a cool animation from the mass properties screen in Solidworks that shows the dynamics of the balance on these engines...before and after.

This post is not just going to be a pitch to sell some nice engines...there will be a lot of usefull info for everyone.

Jim

 

[Creative Engineering]

my original BGF engine and replacement crank both were 3 part cranks (2 counterweights and pin) no m6 screws here. Mine appears identical to the one in the picture except my pin is hollow. -Justin

Interesting my BGF crank has weignts that are attached with screws...There must be a crank maker in China that supplies some customers, and not always the same ones.

I would sure like to know where I could get solid cranks...There is one advantage to bolt-on weights and I'll describe it in the post.

Jim

 

[europorsche914]

Interesting my BGF crank has weignts that are attached with screws...There must be a crank maker in China that supplies some customers, and not always the same ones.

I would sure like to know where I could get solid cranks...There is one advantage to bolt-on weights and I'll describe it in the post.

Jim

I just searched all of Bgf's listings on ebay and did not see and crankshafts but when I had decided to replace mine crank due to my stupidity of attempting to balance my old one (really screwed it up), I asked BGF through ebay if he had any replacement cranks and he created a listing on ebay for me. cost $45 with shipping... My friends Power Kings engine has M6 attached weights. -Justin

 

[Brains]

Hi Jim, No I machined it up myself, no bolts so what ever, Its pressed fit together, still a pilot project of mine, I am in the throws of purchasing a new engine Dyno for 1 - 100hp engines from the US, as the one I have now is rated to 2500HP & its just not accuarate enough on such small HP engines, but I have mounted knock scensor on the crankcase & no evidence of knocking so what ever.

All the engines I will build wether a stock motor or modified to individual customer requiremts will come with Dyno sheet, this way I will run the little babys inn on the Dyno & can ensure my customers just need to bolt on and have no worries about having to run the motors in, the Dyno's these days are simply fantastic, the computer sofware enables me to create individual files for diffrent applications in regards to running inn and for that matter any test cycle I want to do.

Its a huge investment Jim, but we are very passionate & serious about what we are doing, I have to blame my 13 year old son to getting me hooked, as this all started when he purchased an engine kit a year and half ago, I guess he can continue the legend into the future

 

[Creative Engineering]

Hi Jim, No I machined it up myself, no bolts so what ever, Its pressed fit together, still a pilot project of mine, I am in the throws of purchasing a new engine Dyno for 1 - 100hp engines from the US, as the one I have now is rated to 2500HP & its just not accuarate enough on such small HP engines, but I have mounted knock scensor on the crankcase & no evidence of knocking so what ever.

All the engines I will build wether a stock motor or modified to individual customer requiremts will come with Dyno sheet, this way I will run the little babys inn on the Dyno & can ensure my customers just need to bolt on and have no worries about having to run the motors in, the Dyno's these days are simply fantastic, the computer sofware enables me to create individual files for diffrent applications in regards to running inn and for that matter any test cycle I want to do.

Its a huge investment Jim, but we are very passionate & serious about what we are doing, I have to blame my 13 year old son to getting me hooked, as this all started when he purchased an engine kit a year and half ago, I guess he can continue the legend into the future

It's sounds like you're on top of things!

I would recommend that you buy a Dyno in the 1-20HP range. They are notoriously inaccurate in the bottom and upper ten percentile. A 1-100 dyno would barely come alive with one of these engines attached.

Fortunately, for me, the investment in equipment to make bike parts wasn't a concern. I already have a fully equipped machine shop. I have made engines, and occasionally still do, from raw stock.

These are fun, especially for us guys that can make things...the chinese give us just enough to where we want to do more...

Jim

 

[Brains]

Hey Jim, I can undestand what your saying, you right about accuracy, I have ordered an electric eddy current AC Absorber for addaption to Dyno when testing these engines, this way it will be super accurate, I can substanuate the purchase cost for the Dyno this way, as it will be primarily used for Dyno testing with toroidal flow water brake absorber, for when I will be undergoing Dyno tests on the billett engines I have developed for Jr Dragster, It would be pointless investing 25K US for Dyno just for bike engines, my accountant would fall of his chair

Brains

 

[dvddtz]

Hey guys, what do you think the best thing would be to do as far as performance, without having all the fancy equipment?

 

[Brains]

Hmmm, I would start at exhaust mods

Brains

 

[Creative Engineering]

Hey Jim, I can undestand what your saying, you right about accuracy, I have ordered an electric eddy current AC Absorber for addaption to Dyno when testing these engines, this way it will be super accurate, I can substanuate the purchase cost for the Dyno this way, as it will be primarily used for Dyno testing with toroidal flow water brake absorber, for when I will be undergoing Dyno tests on the billett engines I have developed for Jr Dragster, It would be pointless investing 25K US for Dyno just for bike engines, my accountant would fall of his chair

Brains

"my accountant would fall of his chair"... Yeah mine too!

You'll have a perfect Dyno set-up for both applications!

A few years back I was going to build my son a Jr. Dragster...Then I looked at the NHRA rules...there wasn't any shop fun left in the rules. If I could have made my own engine I would have been all over it!!!

Jim

 

[mechanickid]

wow i never thought perfecting these engines could get so complicated!

why not just buy a pocket bike motor for less than it would cost to fix half the stuff wrong with these, get a better product (right?) and be legal?

like this one i guess. (no im not the seller or his sales man )

eBay Motors: Pocket Bike 49cc 47cc Motor Engine and Carburetor NEW (item 330308850062 end time Feb-25-09 06:33:12 PST)

 

[junkyard]

wow i never thought perfecting these engines could get so complicated!

why not just buy a pocket bike motor for less than it would cost to fix half the stuff wrong with these, get a better product (right?) and be legal?

like this one i guess. (no im not the seller or his sales man )

eBay Motors: Pocket Bike 49cc 47cc Motor Engine and Carburetor NEW (item 330308850062 end time Feb-25-09 06:33:12 PST)

i used a pocket bike motor without the add on that one has....took it off my pocket bike


problem is theyre made for pocket bikes and not bicycles....theyre too wide....unless you rack mount it.....i have a spoiler with the 4.25" back rim and its still too wide....i had to run it without the pedals

 

[mechanickid]

ooh. i didn't think of that!

 

[dvddtz]

Thanks Brains

 

[Brains]

Jim, you should have given it a go back then, its great to see the kids faces after a run, its worth a million dollars on its own, The aussie dollar against the green back is crap at the moment & its going to stay this way for some time, the Jr Dragster engines are around 8 - 10K once you bring one over from the states, so its hindering heaps of potential newby's to the sport downunder, as my engine shop is totally reliant on drag racing I thought I would come up with my own engine & chassis set up at a realistic cost, this way it gets future racers into the sport.

mechanickid as for your question about pocket bike engines, yeah they are great, and they hand grenade like theirs no tomorrow as well, I have built quite a few for people & my son has installed one to a bike frame, It goes like the clappas, but in saying this we have done a lot of mods as well, its also very awkward to install to a conventional bike frame, if not done properly it is extremley dangerous & someone is really going to get hert out of it, if you got the time & tools its a fantastic option I reccon, after market components are already out there to purchase straight of the shelf.

My son has just built another for someone & when I get home tonight I will place a pic of his latest pocket bike build, there should be a post he put on himself last year showing the same build, we have perfected it now, he takes it to the BMX track and spins people right out along with me with my heart in my mouth watching him, every time he takes it to the track he gets someone who orders one, I told him once you have built a few you should start a BMX racing class for them, it would be awsome to watch 10 of the pocket rockets fighting for the lead

Cheers
Brains

 

[Creative Engineering]

As Junkyard pointed out...There's always something!

You trade-off one set of evils for another.

The chengine looks like a motorcycle engine...it's relatively easy to install...it's fairly reliable and powerfull.

The pursuit of a better chengine is in essence for the benefit of making a motorbike that feels, looks, and rides really nice.

No matter what the machine...when we operate it we can feel when things aren't quite right.

Jim

 

[Creative Engineering]

Brains,

if you have an unlimited class over there for Jr. dragster...let me know!!!

I'll build you an engine that will be a thriller...and it won't cost anywhere near 8-10K.

Jim

 

[Brains]

I only wish Jim, ANDRA over here is set to max 8.5 at 80mph, break out of this and its instant pack up the trailer and head home, not like the US were you have outlaws

Brains