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fusedminis

Well-Known Member
Joined
Jun 28, 2008
Messages
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Location
Wollongong
Hey Guys,

So I have been looking to do a build like this for a long time now and its finally making some progress.

So far this is what I have:

Frame:
BBR Copy Perimeter
KLX Green Plastics with smaller rear number boards
GPX Forks
Fastace BS-58-AR (looking for an alternate 270mm shock)
RM85 Modified front brake
Protaper Bars
Rear fender brace

Motor:
155z Pitsterpro engine
24mm Mikuni Roundslide (might go for something larger I also have a 30mm Keihin carb but thinking it might be too big)
braided clutch and throttle cables

Looking to get:
Billet hubs and wheels (green hubs, black rims)
Billet GPX Triple clamps (bronze colour)
Dual Exhausts
Rear Brakes
BBR over the top brake pedal (not sure of fitting issues)

Here is a quick look at how its sitting, still have to polish the frame, get a few small details sorted and find some wheels to see how it will sit. I think its going to work out pretty good.

BBRBikesmall.jpg


If anyone has any input that would be great, so far Ive spent less than $1000, and have gotten the larger items out of the way so hopefully everything can be sourced for less than $1500 at least I hope, Im sure it will blow out to somewhere around $2000.

I will be updating this as I make more progress...
 
Should be quite nice by your description... I'd go for a 26mm OKO flatslide carb unless you do some decent engine work, in which case you may want to consider the 28mm (or if you mod like mad you can use your 30mm Keihin) :)

What sort of riding do you plan on doing with it?
 
keeeeeeeeeeewwwwwwwwwwwlllllllllll you seem to have done it quite cheaply
 
I will be keeping the motor stock for now, I will definitely do the retard mod and maybe some slight porting and port matching. I was also thinking of making up some sort of airbox but that will be the last thing on the list.

As for riding, Im hoping my mate builds a new pitty track on his property for all the local boys to thrash around, should be fun.

Does anybody have any experience with the bbr over the top brake pedals, or could someone measure one up so I can make a template and see if it would work, I can get a copy for around $50 but dont want to waste my money if its not going to work
 
There not BBR frames, but I would say they are pretty good, at least this version is, check out this thread for some more info, as its pointless me retyping it all here:

http://www.miniriders.com.au/minibike-builds/26645-china-syndrome.html

There are some problems that have to be overcome, like getting everything to fit, ie the headstem bearings, rear brake master cylinder, plastics and other typical chinese problems.

But as for strength, they seem to be bulletproof, the aluminum is real nice and solid, thick where it needs to be and will polish up real nice.
 
on this frame all you need to do to hid yuor airfilter is get one of this manifold plates that lets you put your carby in different positions and make it so your air filter is right down the middle of the frame
 
This is a half arsed effort of designing some graphics for the bike, hard to tell if they will work, and not sure if I like them enough yet. Still need alot of "finishing" touches.

Picture1.png


Give us some feedback
 
hey fused
looks like you have the same frame as i do,
heres a few things to keep in mind ive found so far
I just put a oko on mine and the choke is a bitch to get to !!! (not impossible but a pain in the arse)

Theres a mob on ebay that sell dual exhausts for these frames but it will set you back over 200 bucks and even then i think you might need a remote resivoir rear shock.

Oh i find the air filter runs very close and sometime even touches the exhaust which can burn through the filter.
And you may have trouble with the clutch arm hitting the frame, ive been told you can heat and bend them but this makes the clutch stiff (have been told a hydraulic clutch may help with this.

good luck with the build man hope i will be keeping a close eye on this thread to see how you go cos i wouldnt mind doing some of these mods myself
 
Hey Bigd,

I have mocked up the new pitster 155z engine that will be mounted in this bike and you are on the money, the arm does hit, but only by just, I have bought a new bolt with a smaller head which hopefully do the trick, otherwise I will be relocating the clutch cable mount and grinding bits here and there before it clears.

Another thing you need to watch out for is the headstem bearings are not the usual ones found it most other bikes. You need to use crf50 ones, but then have to either shim or remachine the stem as it will be different.

I was looking at the duel exhausts on ebay, Im not sure if it will be a direct fit and whether it is a true 32mm pipe. Both are important and for the $200 its a big call to make.

Could you post a pic of your carby arrangement I have one of those discs which allow the carb to be rotated but its on another bike. How hard is it to get to the choke???
 
Fixed the clutch problem this afternoon, a couple of simple bends with the new bolt and presto now the clutch is free to move. I will get a pic up sometime soon.
 
Hey Bigd,

I have mocked up the new pitster 155z engine that will be mounted in this bike and you are on the money, the arm does hit, but only by just, I have bought a new bolt with a smaller head which hopefully do the trick, otherwise I will be relocating the clutch cable mount and grinding bits here and there before it clears.

Another thing you need to watch out for is the headstem bearings are not the usual ones found it most other bikes. You need to use crf50 ones, but then have to either shim or remachine the stem as it will be different.

I was looking at the duel exhausts on ebay, Im not sure if it will be a direct fit and whether it is a true 32mm pipe. Both are important and for the $200 its a big call to make.

Could you post a pic of your carby arrangement I have one of those discs which allow the carb to be rotated but its on another bike. How hard is it to get to the choke???

hey fused
Im thinking if your still thinking of a dual exhaust and run an oko there will be nowhere to fit the larger air filter without burning . so another exhaust may be a better option.

The choke on my bike runs just on the inside of the frame so to get tto the choke its a matter of going in blind reaching uderneath the frame feeling for the choke and pushing it up.
To push it down i have to hook my finger over the top.
Its a bit of a pain but its still worth it as far as im concerned.

As far as the exhaust burning the air filter ive used the angle on the filter to angle away from the exhaust so now sits about 1cm away from the exhaust (I learnt to do this the hard way after burning a hole in my filter so i sugest you do this before firing up your bike)
I'll try and get some pics up this arvo

The other thing you may have a problem with, especially if your gonna use the 360 degree manifold adapter is that the carby may not fit underneath the tank, so you may need a spacer or somtnig to lift the tank for it to fit.
i didnt have this problem cos Im running a different tank and plastics

good luck!
I look forward to seeing your pics of your clutch arm mod.
let me know if it makes the clutch alot harder to pull?
oh btw that dual exhaust isnt 32mm cant remember exact measurement but its not much, if at all bigger than a stock exhaust, that the main reason i opted against one
 
Last edited:
Thanks for the info.

The clutch works fine, the only thing Im worried about is the additional torque it places on the cases and bearings (or whatever arrangement the engine runs) due to the extra height, as for pull its the same as I did not decrease the lever arm.

I think the area for the carb/exhaust/air filter is the next of my problems, Im sure I can work something out, maybe I will use some sort of Uflow arrangement to get the airfilter out of the way.
 
No worries glad to help
Uflow sounds like an interesting idea.
whats your thoughts on your exhaust ? not much around for these types of frames unless you want to spend heaps of cash on a genuine BBR
 
Its either spend big, or go for a copy, the copies are still quite expensive as they are only available in the US so postage kills you.

I think I will be getting the twin exhaust and hopefully it fits, otherwise I will have to mod it up.
 
Made a little more progress tonight, got the cradle mounted up, man what a pain in the bum, couldnt get it to sit right on my new 155z, must have bigger cases or something as I had to grind a few spots to get it to fit.

On another note, I noticed that the engine had carbon in the exhaust port, meaning it has been run??? Are all engines started before they leave the factory, or is this a one off thing? And could someone shed some light into why there is 160cc printed on the barrel, could this engine be a 160ho (I know they are actually 155cc too but something to do with marketing hype)

Im really confused at the moment.
 
i dont think it should have been run..

and for the 160 barrel.. thats normal on these engines as i think the factory were producing 160's at the same time as 155.. the only difference is the crank (55mm stroke) and the head design
 
Will be asap, just havent had my camera on me whilst working on the bike, I will get some up as soon as I can. Watch this space.
 

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