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madmso

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what can i do to my mso 140 to get it screaming its nuts of i have already changed the oil slinger but what elese can i do to it
 
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power 2 weight ratio is the best so loose some weight fatty!!
 
hey how do you make you picture show when you post a comment
 
so what are the options that i can do to the engine still learning all this shit ay
 
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money

yeah well either way ya look at it it all costs money to get more grunt, im in the same boat man and im just undecided wether or not to ditch my 125cc ducar for a 150 or what. theres a local bloke in sa that has ported a 140cc yx motor and put a decent cam in it and a good tune and it beats the stock 150s getting around
 
yeah i dont mind spending a bit ay just dnt know my options and were i can get it done in QLD
 
put a Z40 cam in , bore the barrel up to 57mm and get an akunar piston, port the head, get a quality carb...the list is endless!!
 
yeah sounds good just dont know were to purchase the gear though
 
some easy mods to start with ,is tune it ,get quality leads ,plug ,up an inner rotor in ,polish the maifold,get a quality carby

start there then you'll just want more and more till you run out of coin hehehe
 
what can i do to my mso 140 to get it screaming its nuts of i have already changed the oil slinger but what elese can i do to it
With simple and cheap mods, I had my Lifan 140 going very nicely (before I cracked the case due to kick starting kickback issues). I never took the cylinder off, or split the case. IE, crank, rod, piston and cylinder were never modified.
1) Alum oil slinger. It'll spin up so much faster. I never touched the stock magneto.
2) OKO26 carb. Jetted for good response and inlet port matched up.
3) Fuelstar TM-VC device in the fuel tank.
4) Akunar A1 6.7mm (bottom end) cam. Get the A2 6.7mm lift if you want to trade some bottom for top end. Either way you need to dremel a little alum arc in the piston crown for the inlet valve lift.
5) Akunar valves and springs. New stock metal/fiber head gasket.
6) Mild hand sanding of the ports when the valves were out.
Net result was an engine that let you drive the rear wheel pretty hard on demand in any reasonable engine RPM speed. A lot of fun and double the go of the stock Lifan 140. It had a large exhaust. I also used taller than usual 15:39 sprocket gearing. FYI, I did not like the idea of a top end biased cam on the 140 "stroker" engine. This spec engine was good - on a typical MX track you'll need reasonably good mini suspension, handling and tyres to be able to put to good use.
 
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I forgot to mention another mod I had to do.
7) Stiffer clutch springs. Also from Akunar. After the eariler mods the engine torque is enough that the clutch can slip a lot if you fan it out and hold the throttle open under heavy rear wheel load. In sand the clutch would slip "forever" if not careful (ie. throttle down and shift down then back up).

And one other point to note. The piston dremel job is not too hard. Just copy the shape in the crown for the exhaust valve. Do it with piston in cylinder at TDC. The alum filings can be blown away and are not too abrasive in any case.

btw: The stock cam in the Lifan 150 has about 6.5mm lift, and the stock 150 piston already has cutouts for both valves. With my 140 head and A1 cam on my 150, the clutch also began to slip. So I assume the A1 has a higher peak torque than the stock 150 cam. Downside of the A1 is less top end HP but overall power spread is unreal.
 
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