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beeness

Member
Joined
Oct 16, 2023
Messages
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Location
Australia
Gday this is a thumpstar frame that i'm currently building up from scratch, with help from a donor bike that i have been playing with beforehand.

Thumpstar billet hunge frame
YX140 full manual
Nibbi throttle
VM26 chinese
ASV levers
CRF50 plastics
Woody graphics
Miniracer bars
12"/10" wheel combo
Dunlop MX53 geomax
L'otta fun!
List updates as we go

Started off looking for a frame and subframe kit, had to source this frame from down south.
Got this box shipped up to the Northern Territory

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When it arrived at the workshop, took it out of the box and as expected she was a little beat up, but thats used parts for ya. Not complaining.
These frames were release around 2004-2006 according to the official Thumpstar website.

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Straight away I dummied these shocks, they were abit long but they will do now for the test fit.

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Some parts were a little worn out but it'll do for now.
A nice new BBR pro comp swing arm would go well in the future!


Here is the donor bike, previously was riding this, was a good little base to practice on before hand.

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Got to work quickly the next morning. It had taper bearing conversion on the head stem, so I had removed the bearing races with a die grinder.
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Great success, removed and refit the ones that my tripple clamps took. Which were the less superior crf50 ball bearing style ones.
I reused my original ones.
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Got the tripple clamps 550mm USD forks and the DNM rear shock on.
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Quickly slapped the front 12" wheel on.
I believe 12" wheel is a bit big for 550mm forks, it'll do for now.
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The rear end...making the thumpstar 12mm axles adapt to 15mm axles

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These chain block adjusters were originally 12mm like the one on the left.
I was working with what I got and I bored these out to 15mm
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Big enough for the flange on the axle and nut to fit.1000003104.jpg
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The blue lines on the swing arm had to be filed down.
I know these chain block adjuster are dirt cheap on ebay, but it'll do donkey!
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There we go, fully rolling! Happy days!
The rear axles were too short, so i had to order ones that fit properly.
12" front and 10" rear 🤙
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Whacked the YX140 into the frame. Cant believe how light and basic these pit-bikes are !
Took about a 5 minutes, nipped up all the engine mount bolts, mounted the fuel tank and the front fender.
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Everyones favourite time! Put on the plastics, looks the part now!
Dummy fit the exhaust, a genuine yoshimura exhaust would be great.. dear santa.
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Next was the wiring!
So I tried to make this wiring neat as possible.
I shortened up the loom in every direction and added deutsch plugs. Waterproof and high quality!
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Made up a little aluminium bracket for the CDI. Folded it up in the handy vice, cut to size and finish it off with a 316 stainless bolt. Easy!
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CDI all mounted up.
Having the plug facing down will stop water pooling and corrosion.
I did use dielectric on all electrical pins and plugs.
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Righto, so its time to sort out rear brakes.
Didn't have that much space to work with and very fiddly.
Mounting holes we're already there, so that was a plus.20240820_215819.jpg

Heres the brake master, its pretty long.
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To make it all fit, I had to shorten up the shaft. Blob of weld hope it holds up. Couldnt actually crank too much heat in it'll melt the brake master.
It'll be okay, have faith.
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Had to fabricate up the dog leg on the foot pedal and reinforced it best I could.
Its rusty because I actually took it out for a bush ride to see if it holds up.
What can I say... it holds up !
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Another crappy photo of it. It all survived after a few days of thrashing in the bush.
All this is to be pulled off, cleaned up and a lick of paint.
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The new master mounted, prick of a job.
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New master, braided brake line, and caliper was a kit off ebay.
Other than shortening the rod, it fit straight up to the bike.
Cant complain really, its a win 🏆
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Got some new plastics and some graphics off ebay.
Ran the crf graphics for about a year now, time for a change !
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As you do, acetone up the plastics before applying the graphics.
Didn't use a heat gun this time around 35°c + weather is hot enough for me!
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There it is, they're on. Looks the part!
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Had no excuse not to put the old plastics onto the old frame, saves wasting space somewhere else.

I have the original 110cc engine pulled apart on the bench. Soon to revive it for another build !

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Heres a vid with all the little rigs together.
Blue one- Pitserpro LXR anima150
Green one- Braaap ss125 klx110 plastics and registered

Let me know if you want to see more builds with these, i do have plans !

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Went for a ride the other day, goes well but there are a few things that need changing.
-Rear shock too stiff and incorrect length - Eyeing out a DNM 265mm 250lb perfect for the A-frame swing arm
-Front forks are too short for the 12" rim - have ordered 660mm fully adjustable ebay jobbies, should go better with higher quality fork oil 20241015_110345.jpg

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One of the few bush tracks that I ride 🤙🤙🤙 Goes clock-wise
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A day after the ride, I thought i'd give the carby a clean. Found this plastic spacer between the manifold and carby to be brittle and falling apart.

However did notice during the first 5 mins of riding it was running strange, popping and abit of a delay.
(This carby kit is only about 5 months old so it goes to show how low quality these parts are! Keep up the maintenance on it)

Deleted it and see how it goes the next time!
Will have to order a higher quality foam filter- UNI filter 🤙

Oh well, back to work for 2 weeks, gotta love FIFO work !
See you in 2 weeks ! 20241016_193016.jpg20241016_193011.jpg
 
Thanks man, its a great frame, nice billet piece and heaps light too !
I'm supposed to be picking one up in a couple weeks with the swingarm too at the mini masters. I can't wait lol
 
Had no excuse not to put the old plastics onto the old frame, saves wasting space somewhere else.

I have the original 110cc engine pulled apart on the bench. Soon to revive it for another build !

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Heres a vid with all the little rigs together.
Blue one- Pitserpro LXR anima150
Green one- Braaap ss125 klx110 plastics and registered

Let me know if you want to see more builds with these, i do have plans !

View attachment 16468
Yeah man put the builds up, it's a bit slow on here but ppl still look and occasionally comment lol
 
Yeah man put the builds up, it's a bit slow on here but ppl still look and occasionally comment lol
Yeah ill build the other frame up and put it up on here.

The lxr ill put crf70 plastics and graphics

Since we cant register crf50s or 70s in Aus. Ill make the braaap smaller crf50 fullmod style for the road
 
Man I wish here we could register as easy as some states in America, I'd love to ride a 12/10 around the streets legally lol...looking forward to seeing it mate
 
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Got the 660mm forks on, fully adjustable, compression and rebound.
Went for a quick ride in the bush, soaks up the terrain and jumps so much better, need to change the oil out and dial in the suspension.

Next is a better rear shock, new rear tyre and smaller rear sprocket !
Cant wait !
 
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