Johnson 112 vs 90 questions..

[jimmbo]

If it is a 112 powerhead, perhaps it isn't?

 

[racerone]

Simple -----Remove a bypass cover.-----Measure and post what diameter the intake ports are.------Remove a high speed jet and post the number off it.

 

[ct1762@gmail.com]

the rings, in my opinion, are more broken in then they ever will be after just 6 gallons of gas or so. lots of on-off throttle and stay away from prolonged low speed operation. the 112 and 90 are almost identical... until you hit 4500rpm or so. then the 110-115 (bubbleback) really walks on the 90. its definetely significantly faster, or should be. I agree check to make sure its really a bubbleback 112 with the larger 1 5/16 carbs.

 

[bwilson2626]

Simple -----Remove a bypass cover.-----Measure and post what diameter the intake ports are.------Remove a high speed jet and post the number off it.

Racerone, is thar the only way to tell if the powerhead is actually a 112? Don't get me wrong, I do want to know what the engine is, was just hoping for a less involved way of verifying.
I will definitely do as you suggested if there's not an easier way.
It is for sure a bubble back, btw..

 

[racerone]

Bypass cover is 6 wee bolts and a $4.00 gasket.----Not an " involved " inspection in my opinion.

 

[bwilson2626]

Bypass cover is 6 wee bolts and a $4.00 gasket.----Not an " involved " inspection in my opinion.

Is this what is called the "bubble back or turtleback"?

 

[saltchuckmatt]

Is this what is called the "bubble back or turtleback"?

Yes.

 

[bwilson2626]

Yes.

Also, just confirmed the carbs are stamped 1 5/16