Head. YX140/149 RED TAG RACE 19 BHP HIGH COMP OR STANDARD SQUISH BAND

Head kit YX 140/149cc

We have both types of valve cover heads in stock ready for dispatch.

Here’s what's in the deal

• Fully gas flowed head. Red TAG
• R11 Race valve springs. 40psi
• 27mm and 23mm Valves.
• NBR Race Cam
• Rockers and shafts

We now offer this RED TAG Head with 2 types of squish.

1. Stock cut out type “will only come in as bolt valve covers”
2. High comp small squish

Recommended carb to use

The head can be used as a replacment for all the big valve engines that had the 27/23mm valves.

Will work with Lifan 120 140 150 stock pistons
 

Best carb to use is 3548

We recommend you don’t rely on the timing marks and set valve timing via LCA, they way it prevents valve damage and will give you the best performance. Reason is some engines have the crank sprocket pressed on not 100% correct.

You need a minim of 2mm piston to valve clearance 12 degrees before and after TDC on both valves, any less you will have piston to valve contact at higher revs resulting in a valve dropping.

Red/Blue TAG head 140/150

This head should be fitting by a professional, specialist tools required.

Valve clearances Inlet 3 thou Exhaust 5 thou

Head torque 12 ft-lb’s” Oil nuts and threads”

Cam timing don’t rely on OE marks as they can be wrong, dial cam in 105 degrees LCA both inlet and exhaust.

We recommend you change the cam chain and all 4 rubber components relevant to the cam chain tension, and only run mineral oil to prevent the rubbers going hard and breaking up.

Valve float caused by the above cam chain tension will result in exhaust valve making contact with piston.

Check piston to valve clearance at 12 Degrees before & after TDC you need a minimum of 2mm

Re check head torque after first heat cycle

Failure to do above can result in valves clipping piston and eventually bending or dropping valves.