alfotuning Posted May 20, 2014 Share Posted May 20, 2014 hi all recently done a top end rebuild on my dt std piston runs fine only done 3,000 miles but Im thinking of putting a 170cc kit on :-) for more power i always see people on YouTube poping wheelis in 3ed although mine won't. a 170cc Is around £400 for cylinder piston rings ... i understand how it all bolts together. What Im confused about is changing carb and jets to run corectly obviously i dont want to fit all new piston and blow it up or damage it. also will it need to have the oil pump changed with a 170kit will it need more 2 stroke oil? if i can't use std carb because i won't run correctly what carb will.fit ? Any help would be very helpful. even more helpful if your running a 170cc kit in your dt.could you tell me what its like? than you 1 Link to comment Share on other sites More sharing options...
blackhat250 Posted May 20, 2014 Share Posted May 20, 2014 Its tricky to set up a 2 stroke when its been modified, go up on the main jet a couple of sizes, , and run it in propper, check the plug colour after a short blast, but dont go wide open[ for long] till you see plug colours, Link to comment Share on other sites More sharing options...
alfotuning Posted May 21, 2014 Author Share Posted May 21, 2014 so you say changing jetting on standard carb will work ? also what about the pre mix oil system leave it or does it need more oil ? Thanks for the reply ( Y) and spark plug color should be like what? Also how do you set it up when running in engine like just rev lightly? thank you. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted May 21, 2014 Moderator Share Posted May 21, 2014 If you dont touch the exhaust or the air filter the jetting really wont change by much. The kit supplier, if the kit has been reasearched properly should be able to give you reliable base figures. You run an engine in by riding normally. All that '500 miles at 4000rpm' slowly crap does is take time. Dont have a 'whats it do' blast for a bit and stay away from constant wide open throttle, but that goes for 2strokes anytime. Adding more oil can be bad, if you increace the oil your taking space for petrol or air. That can lean the mixture to dangerous levels. An extra 50 cc will make no difference to the oil needed. Still all the same bearings etc. Piston is only a little bigger. It will be under a lot more load though so dont skimp on the oil QUALITY, with a 170 your asking a lot of that bottom end. So long as you get a nice puff of blue when you crack the throttle open its about right. Once done avoid using normal unleaded, you dont want the ethanol causing you to hole a piston (been there). 98 makes my 250 run massively better. Its not worth the risk. Link to comment Share on other sites More sharing options...
alfotuning Posted May 21, 2014 Author Share Posted May 21, 2014 Yeah i understand I've got full dep! stranded carb everyone says 32mm carb but then i have to fit apower filter and normal air box has to be took of meaning no water trap for.air filter ? so bike probably won't run in rain? is there a carb that will fit on air box manifold rubber to air box and run good? also i understand just thought bigger piston needs more oil but that's good oil pump works fine nice and smoky when cold Link to comment Share on other sites More sharing options...
Moderator Cynic Posted May 21, 2014 Moderator Share Posted May 21, 2014 What do you mean by 'everyone says 32mm carb'. Beware the rumour machine. A 32, 34 whatever carb will work. My 175 uses a 24. The 250 has stoooopid sized 38mm flatsides(i think). It depends what your after. Your stock carb will work and set right will give buckets of low to mid range torque/power. The 32 will give you all the big rpm bang, but you will sacrifice lower range power. There will be a sweet spot. The kit makers should be able to help there. It may well be 32. Generally bigger the carb the peakier the motor, that exhaust will losen a few rpm too, but again losing a little from the lower end. Link to comment Share on other sites More sharing options...
alfotuning Posted May 22, 2014 Author Share Posted May 22, 2014 thanks for help. just was thinking 170 Athena kit but i would rather buy a wr 125 x but £2000 max spending money although all to expensive :-( my dt is worth about 1700 its really clean polish it every week lol. Link to comment Share on other sites More sharing options...
alfotuning Posted May 22, 2014 Author Share Posted May 22, 2014 My dt is nothing like this i dont understand how he wheelies so easy like? would a 170 Athena kit make it more like this? Link to comment Share on other sites More sharing options...
Moderator Cynic Posted May 22, 2014 Moderator Share Posted May 22, 2014 Nope, the 170 just helps. He is a talented rider with good balance. Your showing your youth in impatience. Spend the big bore money on a whelie school, yes they exist im not winding you up. Then you can pop em at will. Link to comment Share on other sites More sharing options...
blackhat250 Posted May 23, 2014 Share Posted May 23, 2014 Sounds like a YZ, deffo been ported,, ,, and just drop the front sprocket 2 teeth, she"l come up easy,, , Link to comment Share on other sites More sharing options...
alfotuning Posted May 25, 2014 Author Share Posted May 25, 2014 it sounds lush its £420 for Athena 170cc kit but people say Athena kit is shit! i dont want to waste money :-\ Link to comment Share on other sites More sharing options...
Moderator Cynic Posted May 25, 2014 Moderator Share Posted May 25, 2014 Well after having an Athena kitted TDR125 sat alongside Blackhat and I at within 10% of 100mph (as per my satnav), with no flat on the tank sillyness, they seem ok to me. Link to comment Share on other sites More sharing options...
alfotuning Posted May 26, 2014 Author Share Posted May 26, 2014 ill probably order it then have a radiator leak always seem to drop water somewhere :-\ also need a new air box bit the rubber what is under seat for air box i cut it and sound different lol probably slower now seem to bog when first rev from idle but can't find a new rubber bit hmm Link to comment Share on other sites More sharing options...
alfotuning Posted May 27, 2014 Author Share Posted May 27, 2014 what jets should i buy 240 250 ..260. Link to comment Share on other sites More sharing options...
Veigar Posted September 9, 2021 Share Posted September 9, 2021 On 5/20/2014 at 8:48 PM, alfotuning said: hi all recently done a top end rebuild on my dt std piston runs fine only done 3,000 miles but Im thinking of putting a 170cc kit on for more power i always see people on YouTube poping wheelis in 3ed although mine won't. a 170cc Is around £400 for cylinder piston rings ... i understand how it all bolts together. What Im confused about is changing carb and jets to run corectly obviously i dont want to fit all new piston and blow it up or damage it. also will it need to have the oil pump changed with a 170kit will it need more 2 stroke oil? if i can't use std carb because i won't run correctly what carb will.fit ? Any help would be very helpful. even more helpful if your running a 170cc kit in your dt.could you tell me what its like? than you I think that shortens the lifespawn of the engine a lot Link to comment Share on other sites More sharing options...
Moderator Cynic Posted September 10, 2021 Moderator Share Posted September 10, 2021 Thread is 7 years old. Link to comment Share on other sites More sharing options...
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