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Posted

hey you may be right, perhaps thats why he changed the exaust. will have a look in the morning :o)

Posted

I can blow through it but you dont get a massive blow through. Have put some tiolet cleaner in it and will power wash it through in the morning. Will also put original carb back on tomos.

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Posted

I can blow through it but you dont get a massive blow through. Have put some tiolet cleaner in it and will power wash it through in the morning. Will also put original carb back on tomos.

well the toilet cleaner may have some effect by virtue of the detergent in it, however if anything that stuff may be mildly acidic to clear limescale from hard water areas caustic is a better thing to clear carbon build up...I would think a better solution (literally) would be a caustic based solution such as sink unblocker, get yourself round to aldi for a couple of bottles of 'Buster bathroom plughole unblocker' bung up the small end and fill it up with this stuff overnight, top up with hot water as necessary...follow this with the power washer and it should shift loads of crap.

Posted

cheers oldgit, ;o). Doing what you said. Have taken a loan out now so may keep it. But also managed to pick up a dt250 so will have something to mess with. Can you tell me standard settings for the carb dt250 mx 1978. Runs ok but feels like its missing around 3000 to 4500 revs. Hit it all the bloody time.

Posted

DT175mx runs much better now :o), very crisp but i am struggling to get it to idle? air screw set 1 1/2 to 1 3/4. It either dies or its above 2000rpm. adjusting the idle screw

Still need advice on the 250mx. Feels like its missing heavily around 3 to 5 thous. Not very crisp either. bit sluggish. Any advice would be great. NewImage.jpg

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Posted

DT175mx runs much better now :o), very crisp but i am struggling to get it to idle? air screw set 1 1/2 to 1 3/4. It either dies or its above 2000rpm. adjusting the idle screw

Could still be carb issues Clive, with a 2.5 slide cutaway it may well be very lean, theres more to it than just the 160 main jet, keep an eye on ebay you will find a carb before too long, when you do ask the seller if it is id 3U500, thats the one you want.

Posted

Could still be carb issues Clive, with a 2.5 slide cutaway it may well be very lean, theres more to it than just the 160 main jet, keep an eye on ebay you will find a carb before too long, when you do ask the seller if it is id 3U500, thats the one you want.

160 main jet, its a 130 standard on the 175 :o )

Thats the carb now fitted m8. with new internals

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Posted

160 main jet, its a 130 standard on the 175 :o )

Thats the carb now fitted m8. with new internals

we seem to be going round in circles here?

early bike 130, late bike 160 i'm sure you have seen me say this in other posts?

not just that though there are all knids of other differences, with the exception of the pilot jet the later carb is richer on all fronts, if your bike has a later airbox then a 3u500 carb should be fitted

ok then for the earlier version

Mikuni VM24SS, Number 2H500

Standard Set up with factory porting, standard exhaust and air filter

Throttle Slide cutaway, 2.0

Needle, 4j13 Clip position 3 from top

Needle Jet, 249 0-2

Main Jet, 130

Pilot Jet, 25

Reed side diameter, 35mm

Filter side diameter, 43mm

Length, 85mm

Float Height, 21mm

Later version for bike with airbox on left

Mikuni VM24SS, Number 3U500

Standard Set up with factory porting, standard exhaust and air filter

Throttle Slide cutaway 1.5

Needle, 4j6 Clip position 3 from top

Needle Jet, 267 0-8

Main Jet, 160

Pilot Jet, 20

Reed side diameter, 35mm

Filter side diameter, 43mm

Length, 85mm

Float Height, 21mm

so you see for example that your 125 carb with its 2.5 slide cutaway is leaner than the early 175 with its 2.0 cutaway, and even further away (leaner still) that the 1.5 cutaway of the later model 175 carb

perhaps this is why you have idle issues and also its risky for overheating and seizure if you run too lean as well you know!

Posted

Mines the first version m8

Mikuni VM24SS, Number 2H500

Standard Set up with factory porting, standard exhaust and air filter

Throttle Slide cutaway, 2.0

Needle, 4j13 Clip position 3 from top

Needle Jet, 249 0-2

Main Jet, 130

Pilot Jet, 25

Reed side diameter, 35mm

Filter side diameter, 43mm

Length, 85mm

Float Height, 21mm

Posted

Well i can only look for air leaks. Not sure what else it can be. I take it ylu judt let the needle slide cut away bit hit the bottom and then ajust throttle bable to suit. Then idle screw?

Posted

sounds good, and have a spray around the inlet and left crank seal with WD40

Its had new bearing and seals but will re check. cant look until tomos

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