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good stuff . now lets see how hot this puppy can get .. lm throwing a leg of lamb on mine , it will roast it up nicely me thinks..
 
Main wiring harness is now modified with a reg/rect, capacitor and new wiring up to the front for the temp gauge, and is all ready to fit.

 
I ran the bike in the shed for a while this morning.
Outside temp was 16°C



Before starting the bike 15°C



After idling for 3 min's, 22°C



After 5 minute's idling, 42°C



After 9 min's idling, 60°C



After 15 minute's idling, 88°C



Close on 20 minute's iding, 95°C
I gave it a 4 or 5 blip rev's over about 25 second's and the temp dropped a couple of degree's.



Turned the bike off and after 1 minute it rose to 101°C, and 15 minute's later it was back down to 45°C






The inlet side Banjo bolt on the oil cooler wasn't too hot to hold at 101°C for 20 second's, and the outlet side bolt was considerably cooler.
The temp's recorded today are with the sender unit fitted into the secondary filter screen plug on the left of the engine, so basically directly below the crankshaft.
I might drill and tap the spare sump plug i have and do another test of the temp's on the opposite side of the engine as well.
 
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Is it possible Daytona conservatively gave the figure of running these engines at 95 degrees to claim no liability in the event of engine failure . They may run at 100 degrees with no problem .. l ll be interested to see if it drops while riding and when the oil cooler kicks in.
 
Yeah i dunno,
I've been doing a bit of research today and found a lot of the scooter air cooled engine's have a 104°C (220°F) limit so i reckon the Daytona's would be around the same limit's.
You can't really make more power without making more heat.
Also when you think about it, the self clean temp for the spark plug is around 450°C up to 800°C so that heat would definately soak back and down through the engine too.

I've read some older thread's on different forum's with rumor's from when the Daytona 4v's come out too, one being that they used under rated valve spring's to stop people over revving them and causing premature top end failure's.
I don't think there's many pit bike engine's that come with a warranty anyway.


I tapped a thread into a spare alloy sump plug i had today for the sender unit,but i don't think it leave's much material between the inner thread and outer thread's.
Might see if i have a spare steel one laying around.
Also after looking in the clutch / r/h side cover, and the port's in the r/h engine case behind the oil pump, i've worked out that the return line from the oil cooler also feed's the port that lead's up to the top of the head and rocker cover spray jet's
So cooler oil is mixed with the other oil coming from the oil pump up to the top end.
Probably the same as the Z160/155, YX150/160 and Lifan 140/150's but i've never really looked at them in detail before.
I think an infared non contact thermometer would be handy for checking the difference between the oil cooler inlet and outlet temp's too.
 
l did an oil change yesterday , inspected the squirt holes and the oil paths. l ran compressed air through the oil system as this is the only way the oil cooler can be emptied out and weep holes from the strainer to the cooler lines. .. Also did a valve adjustment . The oil cooling system is well designed imo .

Also front head stem bearings needed a greasing as there was no evidence or even a drop of the stuff possibly from factory. May of saved them but definitely need replacing soon .
 
All good, How tight were your valve clearance's ?
And when will you take it out again ?


I ordered some new #4AN fitting's last week so i can make up some new cooler hose's.
Thought i may as well go up a size while i'm at it, i have 2 of each fitting on their way and i'll grab some teflon lined hose from a mates' speed shop.


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The inlet valves closed up to .004 and the exhaust gap .006.

This indicates that l need to check every 3 - 4 hours of riding

l set mine at .005 for inlet and .007 exhaust

Daytona specifies adjust when needed. l now know from last time around no more than 4 hours.

Hopefully getting out in the next fortnight
 
I took my Braaap out north on the weekend and had a ride at gottagetacheapyhobby's place, cheer's Stu!
The big girl didn't like to run in the heat up there.
Saturday it was warm at around 35° C, my bike wouldn't run with out spluttering in the upper rev's so i swapped out the #110 main for a #107 and it was a pig to start.
Eventually got it going and headed off for a ride it felt ok but i thought i'd give Stu a ride to see what he thought.
The bike was a total pig to start again, it took over half an hour to get it running.
This was with a heap of kicking from both me and Stu, and eventually it fired up and ran after a long down hill roll start.
I listened to it as Stu was riding and the 190 was popping and almost back firing through the carby so it was retired for the rest of the day.
Next morning i fitted the #110 main back in it and it started pretty easy again, although the PW was also having problem's so i didn't get the chance to try it out again.


This 190 / PWK28 is very fussy on it's jetting, it wont run with 1 jet richer or 1 jet leaner
 
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It blew me out just how fussy that pwk28/190 combo is! I remember last time you were up it wouldnt run with the 115, only the 110. Then this time the same but going to the smaller jet instead.
That 190 really needs a decomp cam, talk about a leg killer!
 
They are really hard to tune with the PWK.

In saying that Chris has his absolutely spot on. It's an animal when tuned compared to the PE.

Will get him to jump on and give settings.
 
Sorry no video's,
I'm still trying to find a cheap/reliable camera (under $150)
And my cameraman (eldest son) wasn't allowed to come outside cause my wife said it was too hot :hache:

Next time for sure though
And i'll try and get a pic of the 6'+ red kangaroo that make's 'Come at me bro" look like a pussy, and some pic's of the brown snake's and goanna too
Just make sure Stus' wife has a big rock in her hand if the roo's close !

thumbs_buff_kangaroo_come_at_me_bro.jpg




My 190 run's fine at cooler temp's, it was pretty hot up there on the weekend though
 
What temps was the bike running at ? l know it was hot just interested how hot the 190 can get .

You may want to ditch the pwk for the Pe . Mine starts 2-5 kicks no mater what the temp is .
 
It start's fine cold with the PWK, 1 kick with the choke, then turn the choke off and it start's first kick
Hot usually 1st or second kick.

I didn't get a chance to hook up a battery to it, i couldn't get the reg/rect put out any power.
I need to test it to see what sort of reg/rect it is and what orientation the wiring is in and out too.
When i got those reading's at home it was using a 5Ah SLA battery
 
I picked up a new carby yesterday, a new old stock Oko 30mm (7 year's old)
Quality is average at the best, the casting is a little out and the machining is so so.
I've spent a couple of hour's on it already smoothing out the intake side, the bell mouth shape wasn't the best.
They're basically a modified 28mm, the top of the throat is bored taller but none of the edge's are blended into the throat, so kind of an oval bore
You can see the oval shape in the 3rd and 4th pic's below
I can see why people have trouble's tuning them, the flow would be all over the place with raised ridge's and taper's, but all that is fixed easy enough with a bit of time put into it.
It'll end up being around a 32mm bore by the time i'm finished blending, and that'll work well for me as i wan't to try and soften the instant bottom end response and torque that the Polini PWK28 has.
Standard jetting in the Oko 30mm is #39 pilot and #138 main's (too small/too big)
This oko has the old style clear fuel bowl which will help me check float level's etc, and it has 4 screw's holding it on which is a lot better design
I'm not sure if i'll try it out before i mod/blend the bore of it, will have to see how much time i have spare








 

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