Honda Spree and Elite 50 Forums

Keeping Spree Elite Aero 50cc and Gyro Alive!
It is currently Thu Jun 21, 2018 10:49 am

All times are UTC - 5 hours




Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Sun Sep 13, 2009 2:38 pm 
Offline
Veteran OG
Veteran OG

Joined: Tue May 22, 2007 7:10 pm
Posts: 3460
Location: North of Seattle, WA
4th up - Higher end dual thermometers
Moving up from that $27 dual channel thermometer gives increasing functionality:
  1. Dual Display show both readings
  2. Min/Max and internal clock capture the value, and what time it was recorded
  3. Can work with multiple types of thermocouple wires J, K,T, E, N, R, S.
    That's handy if your bike is already wired for a CHT, but uses something different than a 'K type' thermocouple
  4. Logging function. Manually trigger storage, or set up a periodic timer to capture samples
  5. PC interface - download logged data for review, processing and display

Image
Fluke 54-II
$369

Temperature accuracy
Above -100 °C: J, K, T, E, and N-type: ±[0.05% + 0.3°C]*
R and S-type: ±[0.05% + 0.4°C]*

Advantages: Fluke quality, accurate, easy to use, settings are persistent. 1000hr battery life. PC software is not required to review logged data, but convenient.

Disadvantages: Fluke does not include the PC software and IR adapter in the price. That accessory is around $180. Second meter itself is expensive. There are competitors which make logging thermometers, include the PC software, and sell for less. Will post links later. The pictured meter was lightly used, and discounted.

--- Logging example - CHT sensor location ---
Plug sensors are commonly used as well as other mounts around the cyl head. One convenient location is a head bolt. How do the two readings compare? Perfect test for a dual channel logging meter, capturing data on exactly the same run.

Probe installation - Stock 1999 Elite SA50. Rear headbolt, closest to cooling fan. 2nd probe on plug.
Image

Test run - approx 3 miles, temperature readings are logged every 10 sec
Results: Temperature differences between sensor placements are large. Plug sensor recorded temp peaks on hills that the head bolt location did not register.
Image

Second test - different scooter Yamaha QT50
More testing of CHT probe placement. Different scooter, no forced air cooling. Exact same test route.

Probe installation:
Image

Results: Temperature differences between sensor placements remains large. QT50 is running hot, better go find that larger jet in the garage...
Image


Top
 Profile  
 
PostPosted: Sun Sep 13, 2009 2:56 pm 
Offline
CBR1000RR
CBR1000RR
User avatar

Joined: Mon Jul 23, 1973 9:24 am
Posts: 9666
Location: Union, WA.
The temp difference is pretty much what I would expect. The plug is directly in the combustion chamber. The head bolt is not.

But from past experience with using a CHT gauge with a switch for selecting the sensors on all 6 cylinder heads locations of a 2 liter race motor, the CHT will only tell you which cylinder you seized in a 2 stroke application. The temps that cause seizing rise to fast and melt the piston top so fast that the gauge can not indicate which cylinder it is before it has done the damage.

My Fluke multimeter has an accessory plug-in adapter to do the temp probe thing, but I never bothered to get it. The shop always had a CHT set-up available for testing.

_________________
Bear 45/70
Image

'83 Aero 80 X 3
'84 Aero 80 X 3

'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree


Top
 Profile  
 
PostPosted: Sun Sep 13, 2009 3:50 pm 
Offline
Veteran OG
Veteran OG

Joined: Tue May 22, 2007 7:10 pm
Posts: 3460
Location: North of Seattle, WA
Bear45-70 wrote:
The temp difference is pretty much what I would expect. The plug is directly in the combustion chamber. The head bolt is not.

Right, not unexpected. Benefit of the test is to quantify the difference over dynamic conditions.

Bear45-70 wrote:
My Fluke multimeter has an accessory plug-in adapter to do the temp probe thing, but I never bothered to get it. The shop always had a CHT set-up available for testing.

If the adapter your need is not the battery powered adapter in this thread (Fluke 80TK) and looks like the pic below, its just a molded banana plug adapter for the K-type thermocouple ends. You could make your own.
Image

Quote:
The temps that cause seizing rise to fast and melt the piston top so fast that the gauge can not indicate which cylinder it is before it has done the damage.

Right, CHT's are slow, and human response too. For this electronic metering thread, I'm game for anything that can be measured at reasonable cost. EGT sensor is the next thing to add. What else should we look at? Also, are the controls used protecting those $$$ race motors doing their work w/o human input?


Top
 Profile  
 
PostPosted: Sun Sep 13, 2009 3:56 pm 
Offline
CBR1000RR
CBR1000RR
User avatar

Joined: Mon Jul 23, 1973 9:24 am
Posts: 9666
Location: Union, WA.
Actually EGT (Exhaust Gas Temperature) will tell you more, sooner than an CHT.

_________________
Bear 45/70
Image

'83 Aero 80 X 3
'84 Aero 80 X 3

'85 Aero 80
'84 Aero 125 X 2
'84 Aero 125
'84 Aero 125 X 2
'85 Aero 50
'85 Spree


Top
 Profile  
 
PostPosted: Sun Sep 13, 2009 4:36 pm 
Offline
Moderator
Moderator
User avatar

Joined: Wed Oct 22, 2008 4:09 pm
Posts: 10893
Location: Deepinnaharta, Texas
Greetings:

This is where engine tech is today. Even historically rustic Harley-Davidson's current Touring models have a feature to retard timing and even disable their rear cylinder when temps get too high during parade duty. Anything's possible with enough sensors and a computer to conduct everything.

_________________
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
Still Seeking Red PCX-150
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox, Carb and Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 99KPH

:coolcruise:


Top
 Profile  
 
PostPosted: Fri Sep 25, 2009 9:17 pm 
Offline
Veteran OG
Veteran OG

Joined: Sat May 16, 2009 1:32 pm
Posts: 413
Location: Mississippi river valley
Just another data point. I hooked an old thermocouple up from a gas water heater to my dvm and got about 2ma on the 20ma scale and 2.4 mv on the 200 mv scale. I heated it till glowing with my propane torch. Probably melted the works. It is a cheap DVM but probably still has high impedance. :)

_________________
1989 Elite E with 86cc Dio
Rumia 50mm bore, mini-stroker, 28mm Oko, modified m-x pipe, Carbonfiber reinforced frame.

Image
http://www.youtube.com/watch?v=gKSvdjxvBUA


Top
 Profile  
 
PostPosted: Sat Sep 26, 2009 8:03 pm 
Offline
Veteran OG
Veteran OG

Joined: Tue May 22, 2007 7:10 pm
Posts: 3460
Location: North of Seattle, WA
elietedio wrote:
I hooked an old thermocouple up from a gas water heater to my dvm and got about 2ma on the 20ma scale and 2.4 mv on the 200 mv scale. I heated it till glowing with my propane torch. Probably melted the works.

Thanks - That's an interesting idea - will look into it. It's less expensive than an OEM EGT thermocouple.

Also, am looking at a bolt on thermocouple like below. But am not sure it's a gas tight connection between the probe and nut.
Image


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group