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TW 125 experts needed!


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hi,

i just got my tw 125 and was sorely dissapointed when it only did 50mph lol so im on a mission to help my 125 be a real 125 or at least do what its capable of lol

firstly iridium spark plug? good idea? or stick to standard ngk dr8ea...

i want to know if you can do anything with the tw exhaust? can i remove the baffle?

i want to add a filter to the crank case breather and a k and n style cone filter to the carb... will i need to rejet or will get away with just raising the needle up one notch?

i dont want or expext 100mph!!! LOL. i would just like it to go 60 easily and not loose all its power on the slightest hill... after all this is a 125 and can easily do 60 - 70 theoreticaly. and its a four stroke so it should have more consistant torque.

everywhere i look all i see is people saying they want their tw125 to go faster and have more guts and all i see is no answer... there must be some way! and an easy one at that!

so, basicaly if i add a k and n filter and free up the air flow to and in the exhaust(remove baffle/restrictor?) surely this will take it closer to where i want to be?

also would it be worth just putting a 55 tooth sprocket on i know this will make the low gears short/accellerate faster but maybe it will give more power to the infamous fifth gear which does nothing!?

or should i go smaller in size? maybe 45 tooth rear sprocket? what effect?

also i have seen these:(type the following into ebay)

SCOOTER 125 PIT BIKE RACING CDI KYMCO QMB

i think it will fit they supply 2 different connections... good idea?

lastly, in the haynes for the valve clearance settings it gives a tollerance of intake valve 0.05mm - 0.09mm and exhause valve 0.11mmm - 0.15mm... basicaly... wtf!? does this mean i can set the clearances to 0.09 and 0.15 and it will run fine on stock set up? possibly with better performance?

im not looking to spend money other that the filters... i know all the tw sites and parts sources but im going to work with whats there

sorry for the long post and i thank you all for your help and time in advance.

please help/advise. cheers

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ok have you had it serviced? cause ur only doing 50mph it sounds like the engine needs servicing along with the air filter, spark plugs ect

iridium spark plugs wont make any difference on a 125 (well you wont feel any difference)

if it was me id get a straight through exhaust (or take the baffles out)

clean the carb and increase the main jet by 10.5

put a better air filter on it (or use a new standard one, depends if it worked with a free flow air filter)

and lower the sprocket size by 3 or 4 teeth on the rear

that way you would increase the torque and the acceleration, and hopefully it would get to 60 mph or at least 50mph a bit quicker.

i dont think the pit bike cdi will work, plus if it did fit, it could potentially blow your engine.

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thanks mate.. i have done a service myself as in oil, filters, plug etc and im looking into doing the valve cleareance... what do you mean by 10.5 on the jet? please explain. and if you know anything about valve settings please answer my original question on valve settings... many thanks

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  • 2 weeks later...

ok say you take the main jet out the carb and have a look at the number itl say something like 95 for example

what i mean buy 10.5 is add 10.5 to the jet size so 95 + 10.5 = 105.5 which should be the size of jet to go and get (its not an exact science as every engine is differant but its a good starting point)

as to valves i havent got a clue best off getting a manual

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