Build based around DAX KTMC GP50R

GoldenMotor.com

Cameron

New Member
Apr 6, 2013
6
0
0
Texas
Hello!

After months of scrolling through topic after topic I've decided to finally create and account and join in on the conversation. I built my first motorized bicycle from a standard 2-stroke kit on a Schwinn Point Beach. I really enjoyed the learning experience working with, and riding my bike. I've had plenty of experience with fabrication, and I got into all of this starting with my attempt to electrically motorize a bike, (including hand making a freewheel crankshaft with two gears). Sadly, my little china girl was recently stolen, on top of that, when they stole it I had recently broken it down to improve some parts including the gas tank, throttle and CDI, so this guy really screwed me over and got nothing out of it.

I've now decided to go up in build quality as I have recently come into the money to be able to make the bike I really want. I want to build around DAX's GP50R I really like the look, compact design, and what looks like high quality of the design. So... What suggestions does everyone have as far as getting a really good quality, long lasting bike, with high performance (sturdy bikes, CDIs, carbs, exhaust/expansion chambers etc...). I am considering doing my first shift kit on this build as well, but I am not set in any one direction yet, so feel free to give as much advice and direction as you would like.
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
48ccbiker I see a KTM clone right on the front page of his web sight?




Welcome to the forum Cameron! You will love this sight there is no end to the imagination here!!

From what I have heard this is a great motor. I run a Morini model that is very much like it.You can get a sweet Tomar brand after market clutch for it too. The Tomar clutch for these set ups have now become my all time favorite way to go.
 
Last edited:
Mar 31, 2013
295
8
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RI
I looked at the DAX site and could not find that engine. Where did you see it? Wouldnt it come with a CDI?
if you look just to the right of the green bike you'll see the ad copy for that motor along with 2 pictures, one from either side of the motor and in both you can clearly see the kick starter, it really does look sweet.

peace, bozo

here's the ad copy:

Here we have the DAX GP 50R Air
cooled 9 hp power plant. This is an
auto clutch engine with 420 chain
for final drive. 10T Drive sprocket
single speed with auto clutch twist
and go operation. Weighs only
18lbs or so, very compact, 49cc
displacement. Comes with Kick
start, Carb, CDI, and Coil Pack. Mix
Ratio is 32:1. Only $479.99 and
$19.00 shipping. Comes with a 90
day warranty. Allow 5 business
days before Engines or Engine kits
to ship. Call or Order on line !!

Single cylinder, 2-stroke,
air-cooled 48.8cc
Max Power: 9HP/9500RPM;
Max Torque: 7N.M/11000RPM;
LxWxH: 290x220x250 m
Weight 8.9kg
 

Cameron

New Member
Apr 6, 2013
6
0
0
Texas
So I wasn't getting much response so I ordered the clone about a week ago, as well I ordered a micargi 7-Speed men's cruiser, and a 41 tooth sprocket. I genuinely loathe coaster brakes, so is there any way I could replace my back wheel with one that was a single speed (no coaster brakes), I understand this would require resizing the chain. But where it was a cruiser sized tire.
 

dmb

Active Member
Dec 4, 2010
1,354
3
36
lakewood ca
check out headtrama's ktm clone build in the cruiser section. and that's the bike he's racing on the mid class video on the race sec. dennis
 

16v4nrbrgr

Active Member
Mar 17, 2012
1,728
4
38
North Bay
The only issue is that you need a huge sprocket to be geared right. I am running 20" (actually 22" diameter) chopper tires and need a 80t for a top speed of 62, so the drum will spin freely enough for the stock clutch to hook up at higher rpms and get on the pipe. As it is right now with a 44t from a kit, the bike slips away half of its power.
 

headtrama

Member
Jul 8, 2010
886
2
16
california
I am very happy with the way my Ktm clone bike performed. My bike is geared with a 51 tooth rear and 10 tooth front. I am running 26 inch rims and the bike pulls really well with some good top end speed. It seemed like the more laps the bike got the better it ran.
 

16v4nrbrgr

Active Member
Mar 17, 2012
1,728
4
38
North Bay
You might look into gearing because my chopper with a 44 was geared for 110mph, doing so leaves a lot of acceleration on the table because I don't want to go faster than 60. It just grinds away your clutch is your gearing isn't right, wasting clutch and power.

With its current setup I can go 60+ but the clutch doesn't start working right until 15mph and the acceleration is lame. By gearing it appropriately the clutch will work as intended and the bike will get on the pipe and hopefully wheelie.

The KTM50 is meant to run on a bike with like a 60t on a 12" rear wheel, gearing it with regular motorbicycle sprockets will work to make the bike move pretty well, but it will move twice as fast with the right leverage.

I'm going to try Rebel Gears, since King's Sales and Service ignored me enough to not warrant a sale.
 
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headtrama

Member
Jul 8, 2010
886
2
16
california
I feel my bike is geared perfect for racing . It still has enough bottom end to pull me out of the turns well and has a descent top end on it . If you still have the stone clutch in it you must have it dialed in perfect . My tomar clutch works flawless for me and locks up when it is suppose to .
 

headtrama

Member
Jul 8, 2010
886
2
16
california
I got a clutch for the 2004 ktm mini adventure , Its not a drop in and go at least it wasn't for me . I had to turn the primary gear down a little .