What's rong? Exhaust temp gauage

Anything related to Lambrettas... ask tech questions, post helpful info, or just read and learn.
Stian
registered user
Posts: 44
Joined: Thu Jan 22, 2009 11:47 pm
Location: Bergen, Norway
Contact:

Hi!

My RB 25 have "melted" twice. Even the sparkplug have melted. Thats not the case in this tread.

My koso exhaust meter have never shown much more than 400 degres C. So I have done somthing rong.

Any tip?

Cheers
Stian




[imghttp://i1145.photobucket.com/albums/o502/saabstian/eksos2.jpg][/img
Image
Image
mick1
registered user
Posts: 1292
Joined: Sun Dec 04, 2011 7:43 pm
Main scooter: Li Avanti 225
Location: York
Contact:

Hope this link works....might be of intrest...

http://www.iwt.com.au/EGT_CHT.htm
rbgaz
registered user
Posts: 539
Joined: Tue Mar 17, 2009 6:16 pm
Main scooter: gp rb230 dragster 180lc
Location: braintree lambretta breakfast club
Contact:

that probe looks to short to me, the tip i thought is meant to be in the middle , my koso shows egt at about 630c and think it is safe to go up to about 700c , melting point if i rember correct is about 730 ? cht stays at around 160-190 c this is also on a rb
User avatar
coaster
registered user
Posts: 3125
Joined: Wed Jan 07, 2009 12:35 pm
Location: London and Norfolk
Contact:

The probe should be 100mm from the piston skirt, that looks as if it needs to be moved down the pip about another 25mm or so
nelson pk
registered user
Posts: 515
Joined: Thu Jul 08, 2010 12:31 am
Contact:

Your probe should be nearly in the middle of the pipe.

However the main issue is the way you are reading it. EGT's will vary greatly from different set ups for the reasons of 1) different exhaust types (hot pipes, colder pipes etc), 2)distance from piston skirt to probe, 3) how far probe is inserted into pipe (oooh errr missus!) 4) quality of probe (some react to temp change quicker than others).

An EGT is useless on its own without doing plug chops at various temps to see when it is leaning off or richening up at certain temps or having a dyno session and recording the normal operating temps.

There are guideline temps, but i have seeen EGT's vary dramatically from one bike to another.
For example my mates, like yours will run at about 400 degrees when cruising in the mid range, but on mine, if i was cruising in the mid range and mine was reading 400 degrees my bike would be spluttering and fouling plugs all over the place.

Dont rely on EGT's on their own. They are great when you know your bikes normal operating temp but when setting up do plug chops, choke tests etc.

An EGT can read very low when the heat is being retained in the head and piston and not going out via the pipe...........for example on too advanced timing, so too cold can be as bad as too hot!

Remember, its just an indicator, like a cylinder head temp gauge you need to know the normal operating temp of your set up before relying just on the EGT gauge.

Hope this helps!
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: No registered users and 16 guests