Stiff Rennshift
 

I bought the Rennshift from pelican parts the linkage and precision adjuster from Tangerine racing,the gear change up is not that smooth very clunky and when changing down it feels as if the shifter is stuck ,you have to pull it quite firmly ,I have a 914-6 and had hoped all these combined parts would have made for smooth shifting ,what could the problem be

rennshift
 

I think what you have going on is the rennshifter is harder to shift due to it being a short shifter making the pivit point having more of an angle and making it clunk in to gear with more force needed to engage the gear. The 914-6 gearbox is a tail shifter and have always been sloppy .If you want better shifting you will need to upgrade to a side sfift 914- or 916 conversion to get a smoother shifting gearbox. I have had the tail shift gearbox in the past and I like the the side shift style gearbox better.

If you do not have a side shift then you are screwed to put it bluntly! I had one of the first hundred or so made and it was GREAT! Since I raced the 914-6 I had the trans mission out every two years to have an over haul, so you have to start there. Once the side shift trans is like new or better then from front to back you want the Rennshift, one of Jim Patrick's fire wall bushings, then the sealed aircraft U-joint then finally new bushings at the transmission shift rod console. Since where the rod goes through the bushing is usually a tad loose use several small plastic wire ties through with it to firm it up. Make sure the Rennshift is adjusted spot on.

When I raced I could shift into 1st gear at 20 MPH easily in a race which gave me great oomph out of a tight corner. Good luck.