cylinder head temperature

[ed53-+]

1948 panhead , running ok, checked the temp's with digital inferred device , front cylinder at 240 deg f, but the rear is way lower at 135 deg f ,
temps were taken just south of the spark plug hole. any thoughts on this, i'm thinking timing is advanced to much, but bike runs well, starts easily, plugs a tad on the rich side, but i have ordered the smallest bendix main jet available. engine has less than 1 hr running time.
thanks

ed C

[58flh]

ED---Sounds about right!,The front always is hotter--you would think it would be the other way around!,--I shot numerous bikes & your results are fine!--Frequent oilchange & run the carb. a little rich--Strobe your timing if you want -just to be sure & piece of mind.--Respectfully---RICHIE---ED---If your Bendix has an ADJ. main Which it sounds like you don't -(as I got the smallest mainjet they make!)--I should of read it twice!--Pull your PLUGS & make-sure there atleast TAN!--now a COCO-Brown is better.But if there CLEAN & WHITE on the insulaterd -Don't RUN THE MOTOR!---(I would start reaming the main oversize in .002-increments.Until You get a nice burn!--(I like to run mine rich,& my insulaters are black with a coco-brown on the top-crown of plug!-& they wipe easily clean with a finger)-That's just my prefererance A lot like to shoot for a TAN color & that's ok to!--But I like to get whatever I can in the temp.-dept. for cooler running!--Summers are hard on our bikes!.You don't have to keep buying jets,just open it up in precise increments & ADJ. for proper plug color on both cyls.---(This wont mean squat if you didn't BUBBLETEST THE INTAKE SYSTEM!)--The slightest bubbling can drive you nuts!-as it olny gets bigger when shes up to running temp!).So if you didn't Bubbletest with atleast 12psi anything you do will olny be worse!.---(bubble-test & strobe the timing& check your plugs color regularly---This is most important on a fresh motor!---& change your oil about 6-times before you hit the 1000-mile mark,I have been doing this & have good success!---Respectfully---RICHIE

[Mr.Big]

Ditto on what Richie said about temps. I was certain I had a manifold leak on my '52 when I shot those same temps but thankfully never found one and got educated about how much hotter the front runs. My oil temp runs from the mid nineties in cool weather to mid 120's in hot. Still successfully running the hydraulic pushrods as well.

What has your oil temp been running?

[Cotten]

Just ponderin', Folks,....

What if both heads are really the same inside, but the front is where it is escaping most.

....Cotten

[Panacea]

I wonder if a skinny tire with no fender would let the front cylinder cool enough to match the rear temps?

[58flh]

Cotton--As to your thoughts on this ,Im going to check while riding & when sitting still !--Temps. tend to go up as soon as motor shuts down for a few.Ill post my findings At running speed, Stopped & Idling,& finnaly off & take a few reading in the next 15-min.----Richie

[ed53-+]

excellent info guys , will do the bubble test , thanks