Engine temps.

[bigheavy150]

Today i went and borrowed a nice infrared thermometer to check my temps after i did some jetting here is what i got.
all temps are in Fahrenheit

Head: 240-280 hottest on the exhaust side about 240 by sparkplug.
Top of valve cover: 180-210
Cylinder: about 250
Oil: 160
Header 400-600 hottest at the first bend. lowest right where it exits the cyl.
Ambient temp: 80-85

Also my tire temp was 108.5 front and 105 back

its a pretty nice temp gun so im confident in the numbers.Its a new Loncin 162FMJ(150 pushrod) with bout 90km so far running mobil (regular) 20w-50 and premium gas. I putted around town for 15 minuets then gave it a few blasts down a 3/4mile stretch. It seems to pull better both high and low.

I adjusted carb to 3 turns out on idle mix and moved the needle clip down a notch.But my plug still looks white,ashy and hot looking.No more farting out the carb or stalling at idle or nuthing. she will start cold without choke but needs some throttle to keep running.

So what do these temps tell me? everything is good right?

[Cal25]

Too bad you could not have done some tests before doing the jet changes.

My Trail Tech Vapor came with a temp sensor that fits under the sparkplug. What I found was that the temps from there changed vey dramaticlly. For instance, long run at WOT, temp would go to near 400 degrees F. My first thought was if I let off the gass it would cool quickly. Instead the temp shot up another 25 or so degrees almost instantly. (It just went lean) roll on the throttle and it woul cool down just as fast maybe 50 degrees or so.

It did seem that the overall hi temp was reduced by about 5 degrees after I reduced the restrictions in the exhuast and went to a Uni-Filter and a jet change 2 sizes bigger.

I think a oil temp gauge would be most usefull on my bike.

[Barnone]

big,
Interesting temps.

I'm surprised the oil temp was only 160 F. I have one of those dip stick temp gauge for my pit bikes and see oil temps of 240 F on long climbs up the steep logging roads in the mountains of North Carolina. I use Rotella Synthetic oil.

[Weldangrind]

Barnone, can you provide a link to where you bought the dipstick temp sensor? Do you trust it?

bigheavy150, your engine sounds lean. According to waynev:

Just remember that the pilot jet / A/f screw will control the idle mixture ( if your A/F screw is more than 2 turns out you should go up 1 size in pilot jet), the needle jet adjustment will take care of the midrange mixture and your main jet will control 3/4 to WOT.

Since you're three turns out, it's a good idea to swap in a fatter pilot jet. I'd drop the needle one more groove, swap in a fatter main jet and re-test.

[Barnone]

W&G,
I use these temp gauge in my pit bikes not my Q. .
I can't remember where I got my temp gauge but they are something like these from Ebay.
http://cgi.ebay.com/ebaymotors/Pit-D...Q5fAccessories

Seems to be accurate enough.

[Cal25]

I think I saw them on the DRATV website that someone mentioned the other day.

[bigheavy150]

Originally Posted by Weldangrind

Barnone, can you provide a link to where you bought the dipstick temp sensor? Do you trust it?

bigheavy150, your engine sounds lean. According to waynev:

Since you're three turns out, it's a good idea to swap in a fatter pilot jet. I'd drop the needle one more groove, swap in a fatter main jet and re-test.

yes i need a new pilot jet, only problem is finding one, thats not one of the items that italika sells so IDK.
It was much more lean before. I think its a hair on the rich side now at idle. and i may raise the needle again

Also im sure my oil temps would be higher with some sustained speed but the side streets around here are pretty small and crowded. I plan on taking the gun with me tomorrow for a trail ride But i dont think this motor will overheat anymore

[Weldangrind]

I'm stuck on your comment that the plug looks white. That's bad. I'd shoot for grey / tan.

[bigheavy150]

Originally Posted by Weldangrind

I'm stuck on your comment that the plug looks white. That's bad. I'd shoot for grey / tan.

It could be called gray around the ceramic. But i see definite signs of having different mixes at different throttles. The "base ring" near the treads is slightly black. But my electrode tips are white.Not sure what that means.But i like my engines to be perfect mix until 3/4 throttle then i like a bit rich at WOT.

I looking for some new plugs to color up and then i will post pics.

It seems happy,runs cool and has a slight "rolling" sound on decel. and hasnt farted or backfired at all since the adjust.

115km and i have burnt 3L of gas [/i]

[FastDoc]

All I can say is that with airplanes, also aircooled, normal CHT is less than 400. Less than 375 ideal, less than 435 maximum.

Ideal oil temp is less than 180, less than 220 acceptable.

[bigheavy150]

plug pics.




Keep in mind that i have been using it for alot of short trips. like long enough for the cylinder to heat up but the oil usually doesn't get past 150.

[Weldangrind]

My uneducated eye guesses that the mixture is on the lean side, and there is a slight oil control issue. I wonder if the rings haven't fully seated yet. Perhaps the oil is creating a cooling effect.

I'd buy one size larger jet and test again.

[bigheavy150]

Will do, Capn'.
The carbon looks alot worse in the pic then in real life.its just a thin layer and I can just touch it and it wipes off.

Is there any jets from Japanese carbs that may fit mine?I doubt the so called italika service center has them.

you may be able to ID this carb by sight:
http://i778.photobucket.com/albums/y...Picture078.jpg
http://i778.photobucket.com/albums/y...Picture077.jpg

[FastDoc]

Good quality pics. I'd read it as normal, or maybe on the lean side of normal but no intervention necessary.

[Weldangrind]

I agree with Doc, but if jets are not too much of a nuisance to find, it's worth playing with. Always better to err on the rich side, and you might even pick up some performance; who knows.

It's hard to tell, but it looks like a PZ27 carb. I'd be interested to see the jets. I just took mine down to the local bike shop and matched 'em up. FWIW, my local Yamaha dealer has Mikuni jets, while the Honda dealer has Keihin jets.