TB 143, 160 & 165 V2 Race Head Decompression Option [TBW0593B] $115.00 Click to enlarge Race Head V2 Decompression Valve Option – V2 Heads are machined and equipped with a decompression valve that eliminates high compression starting resulting in increased service life and reliability. The decompression valve releases compression in the big bore race engines upon startup so there is no need to start at TDC anymore. It was designed to eliminate common problems associated with high compression starting such as cracked and broken inner cases, broken kicker shafts etc. It's also easily accessible with an extended billet knurled end knob. To operate, just push the knob in prior to starting and kick it over nice and easy and that's it! The V2 Head will come with this option fully installed. Additionally, any existing V2 Head, stock KLX Head, and YX stock KLX type Head can be upgraded with this option for the same price of $115 plus shipping. If interested in upgrading your existing head, please contact our machine shop partner, Jamie, at carbonworks@comcast.net to arrange your head upgrade. This is a special order option for any of the V2 Head kits listed in this section and can delay an order from 0 to 8 days depending on stock. Professionally machined and manufactured in the USA