1. Home
  2. Engines
  3. Tillotson Engines
  4. Tillotson 212R Engine
  5. Tillotson 212R Head & Valve Train
  6. Tillotson 212R OEM Head & Components
  7. Tillotson 225R/RS 27/25 5mm Cylinder Head Assembly w/26lbs Springs
Tillotson 225R/RS 27/25 5mm Cylinder Head Assembly w/26lbs Springs
138220050 Tillotson 225RS Cylinder Head Assembly w/26lbs Springs
Write a Review

Tillotson 225R/RS 27/25 5mm Cylinder Head Assembly w/26lbs Springs

Part Number: 138220050
1 Review(s)
Online Price: $79.99
Availability: In Stock.

Send to:

*We'll ask for shipping info at checkout


The cylinder head is the same JT-207 used on the Tillotson 196R but modified to fit 27mm and 25mm Valves with 5mm stems. 

The 27/25mm JT-207 is the same head used on the Tillotson 212R but includes the spec 26lbs springs used in The Tillotson T4 225RS Spec Engines. The 225RS is an excellent bolt-on head that can support many mild cams, including the MOD2 and popular 265 lift cams, including our Banzai 265. 

The 5mm stems help to reduce weight and friction between the valves and the guides while improving flow. The valves also use automotive-style split locks and retainers.  

We highly recommend racers in The Tillotson T4 or T225RS Classes to keep a couple of extra cylinder heads available. Like the Briggs LO206, the valve seal is crucial for the engine to maintain spec performance. The rev limiting coil and noise reducing exhaust builds a lot of exhaust and cylinder head temperature that can cause the exhaust valve and seat to wear. The valve leak bleeds off the combustion and reduces power and performance. 

Cylinder Head Assembly

- Intake Valve: 27mm

- Exhaust Valve 25mm

- Valve Stem 5mm

- Combustion Chamber 20.9cc

- Rocker Arm Assembly

- 26lbs Springs

- Pushrod Guide

- Retainers & Locks

Related Items

Customer Reviews

JT-207 head is awesome
Awesome head for the money it performs so much better than a stock predator one. You can touch up the ports a little and gain a lot. It came on my Tillotson 212r, I put a billet rod, .010 head gasket not sure what compression is now, Nibbi pe24mm carb and a dyno cam super X .265 cam 232 duration and 26lbs springs, wanted a motor to hopefully be a beater but perform and last so far 3 tanks of WOT around my buddy's dirt oval running 12 62 gearing so far no problems other than clutch dragging a little. But the head Makes Amazing power out of the hole, great torque and still will pull 9k. The intake I have if I'm riding long enough will almost form ice on it the head is flowing so much.
Did you find this helpful?  4 of 4 Found Helpful
Reviewed by:  from CT on 6/24/2023

Recently Viewed Items