TMY's MSO 140S

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fiffty _boytim said:
no if you push a brand new engine to hard they seize ive seen 2 brand new 140s and a 150 engine seize cos they wernt worn in properly
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i would seriously doubt this is a resault of bad or no run in

these engines dont need running in and what run in is needed is in the first 20mins and 10 mins of that is warm up
 
G'Day Lads,

Thanks all for the replys. I've learn't a lot in the past few days due to feedback.

Had a good ride on the 140S yesterday. After a not so fantastic ride on friday afternoon i had low expectations. But i did another oil change and put in 1.3L of Motul1000. Pumped up both tyres and lubricated the chain. The bike kicked over in almost the first attempt and idled with the choke off!! Which was fantastic. It was from then that i knew i was going to have a good day. Anyway, began riding with my mate (he has a genuine 125cc Thumpstar) doing some run in acceleration runs. Everything seems to be running perfectly, only problem i have is that i don't have enough room to stay in fourth for very long. Day was cut short when my mate popped his rear tyre. , was funny though ;)

I've started my shopping list and will slowly purchase over the next couple of weeks.

Subscribe to this thread if you think you can help my with my purchase decisions :)

LTN16 - Thanks mate. :D
 
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Alright,

Just Tried to ride my bike. First of all both tyres were flat, Rear was completely flat, front wasn't far off it. So i decided id just kick it over for 5mins and let it idle. Sure enough it wouldn't kick over. After about 20 or so trys and building up a sweat i gave up.

Any suggestions why it wont kick over? (has plenty of fuel/oil)

Whats the name of the things that prevent my tyres from going flat? Can't recall the name off the top of my head. EDIT: Dw, was referring to Rim Locks.

HELP MEEEEEEEEEEE
 
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pull the spark plug out and check if it has spark. If it does than you have a fuel blockage. It could be just cause its new that it may have some crap in the carb blocking the jets. Rim locks only stop tyres goin flat if you are riding hard and the rim spins without the tyre, ripping the valve off.Pump up your tyres and put a big dob of spit on the valve with your finger,if the spit keeps busting than your valve is leaking. Also if you rode it with not enough presure in the tyres you could have pinched the tube.

P.S. when you say it wont kick over do you mean it kicks but wont fire up or that it physically wont kick over with the kick start?
 
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01nutracing said:
pull the spark plug out and check if it has spark. If it does than you have a fuel blockage. It could be just cause its new that it may have some crap in the carb blocking the jets. Rim locks only stop tyres goin flat if you are riding hard and the rim spins without the tyre, ripping the valve off.Pump up your tyres and put a big dob of spit on the valve with your finger,if the spit keeps busting than your valve is leaking. Also if you rode it with not enough presure in the tyres you could have pinched the tube.

P.S. when you say it wont kick over do you mean it kicks but wont fire up or that it physically wont kick over with the kick start?
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Cheers for the tips.

IT does actually kick. but wont actually start if u get me.

Ill go over the carby on wednesday.
 
i have made an order for a few bits and bits and pieces. Wont clear till next Wednesday, then i play the waiting game for postage.


Stock picture, for comparison in a few weeks :D


HAWKESNEST-368.jpg
 
coolmodee01 said:
i would seriously doubt this is a resault of bad or no run in

these engines dont need running in and what run in is needed is in the first 20mins and 10 mins of that is warm up
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it was eeing as these engines tend to come with uneven spots in the barrel if u go alll out at once you destroy the piston on those uneven bit thats wat we found in 2 of the engines the other was a cam bolt coming out
bike looks good buddy
 
TMY said:
Sure enough it wouldn't kick over. After about 20 or so trys and building up a sweat i gave up.

Any suggestions why it wont kick over? (has plenty of fuel/oil)
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Maybe it's running a bit rich. Try holding the throttle about half open when your kicking it. I had the same problem with mine but as soon as I changed the needle clip up a position to lean it out a bit it has been fine.
 
I think it was running a bit rich.

Just kicked over easily then. Strange, but im not complaining :)

Let it to idle for 5-10mins with choke on, turned it off and it cut out. how long do you guys let your bike idle for? Maybe my idle is to low? thoughts appreciated :)
 
Dude, the carby these bikes come with is crap! I had same problem! I adjusted the needle and it started with chock but had to idle for 5 min before I could rev it! Bought a VM24 carby kit from DHZ and it fired up first time with out chock!! The new carbi is SO much easyer to adjust (Fuel/air) and is in general more suited for the bike! You may go for a 26mm carby since the carby inlet is 26mm! Also get a proper airfilter!
 
01nutracing said:
It could be just cause its new that it may have some crap in the carb blocking the jets.
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how do I check this? I drained the fuel in my carby into a drinking glass and it had little bits of black plastic in it, probably from the fuel tank. I'm installing an inline fuel filter today and gonna clean the fuel tank. how do I clean my jets or anywhere else in the carby that might have the plastic stuck in it?
sorry for the hi-jack :D
and to those who say run-ins aren't necessary, that's gotta be the worst advice I've ever seen someone give on this forum! where's the proof to back up such a huge claim?
 
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londin said:
Dude, the carby these bikes come with is crap! I had same problem! I adjusted the needle and it started with chock but had to idle for 5 min before I could rev it! Bought a VM24 carby kit from DHZ and it fired up first time with out chock!! The new carbi is SO much easyer to adjust (Fuel/air) and is in general more suited for the bike! You may go for a 26mm carby since the carby inlet is 26mm! Also get a proper airfilter!
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Londin I know you dislike the Mikuni "25mm" but I've run my MSO fine on it for over a year and I've recently changed it over to the Pitpro and it runs great with it too. Never hard to start or have difficulty revving without warming up. I have a VM24 on the way though so perhaps I'll see what all the fuss is about when I fit one of those :p
 
I've had no problems with the stock carb either.
I can pretty much turn the choke off as soon as I've started it with no problems..

Adjust your needle clip to position 3.
 
TMY without lookin at the bike its hard to say but maybe it is as simple as the idle being too low. If you dont know how to adjust it its the screw on the right side of carby if its a mikuni copy.Screw it in to increase revs. If this dont work I'd say your pilot jet is blocked with crap which is very common without a inline filter fitted. Take the carb off, Unscrew the bottom off the carb, watch out for fuel , the jets are exposed when you do this, they are the 2 brass tube like things (dont know how better to explain it). The pilot jet is the small one and main jet is the fatter one. Unscrew them one at a time and blow them out as they should be hollow all the way through. Put back together and dont lose the pin holding the float in. good luck
 
Wow guys,

thanks so much for all the help! I'll adjust the idle before i think about changing the carby.

All is very much appreciated :D

Will report back tonight with my progress. I hate checking here then knowing i have to wait till after work to try it all out :)
 
Check this old thread out ... I talked about bits of plastic from the tank among other things :

http://www.miniriders.com.au/tech-talk/14424-oiled-air-filter.html

The thread is a classic case of other people playing "follow the goon" ... The VM-26 Mikuni carb kit he got was from the USA and they are well known to have idiot huge sized jets ranging from 155 up to 190 in size ... MASSIVELY too big for Australia which is mostly at or near sea level ... Since the carb comes stock with a #190 (Mikuni sized jet which is BIGGER than a #227.5 Keihin jet) ... his engine would have been running as rich as a MOFO to start ... (Most 26 mm carbs run great with a #100 to #105 KEIHIN sized main jet in 'em) ... THEN when he oiled the filter , it would have run like the choke was on ... Since the engine was sooooo rich to start of with , it's a wonder it ran at ALL ... the fact that he said it back fired tells me that his valve clearances weren't right either ... A tight inlet valve will cause back firing , hiccing or popping back thru the inlet tract and the reverse flow of gas will make the engine a bitch to start ... and can even make it impossible to start if the valve is being held far enough off the seat ... Under NO circumstances should an engine that has perfectly sealing valves and properly adjusted ignition timing EVER back fire , "pop" or "spit" back thru the carb ... IF your engine is doing THAT ... it needs the timing checked first (cam and igniton) , and IF they are right and the valve clearances are set right ... then the head needs to be removed and the valves lapped and blue checked to ensure they are sealing all the way around the seats ... Too many people blame problems on the wrong diagnosis ... Popping , hiccing , blowing back or back firing thru the intake is the equivalent of a tyre leaking air ... The valves of a brand new engine can quickly sink into the seats and lose their stem to rocker clearance ... making most knuckle heads think it's the carb because the engine won't hold a tune , is hard to start , and won't idle ... The symptoms can be intermittent and in most cases the engine was running perfectly the last time it was ridden ... That's because it was hot which increased the clearances ... but once it cooled down , the clearance gets lost as the alloy of the head contracts ... an bingo ... weird running problems suddenly surface ... One thing is for certain ... carbs don't suddenly go out of tune unless there is dirt or crap fouling up the float valve or blocking the jets ... So the LAST thing you should touch are the screw adjustments and jet sizes if the engine has run perfectly with them set that way before (with a stock engine) ...
 
Note how he say he gave it a "light" coat of cooking oil ... but THEN it was all thru inside the carb "blocking" up the jets ? Maybe oil can run sideways and even uphill ...
 
Photo :

MSO1.jpg


If i take a picture of my carby, would someone be able to help me by pointing out the idle screw? I don't want to touch the wrong thing!
 
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