Thread: When to re-pitch?
03-16-2008, 10:40 PM #1
When to re-pitch?
At what point do you have enough RPMs that a re-pitch is beneficial? Would you say that turning a peak of 7320 in 90 degree weather would warrant an up pitch? If so, how many RPM do you usually drop by a one numerical number up pitch?
03-16-2008, 10:42 PM #2
7150 -7200 is the range your looking for ill be pitching up
What speeds are you at now and mods
03-16-2008, 10:45 PM #3
the ski is a 2004 XLT and has run a best of 74.1, last weekend it went 73.4 in 90 degree heat. It currently has a 15/24 dynafly in it.
03-23-2008, 03:12 PM #4
03-23-2008, 04:54 PM #5
OK I am curious, what cylinders / pistons do you have in that thing?
what temperatures do you do most of your riding in?
what nozzle are you currently using? (85 or 87)
03-23-2008, 05:03 PM #6
The ski has a TJ ported 1390 in it and most of my riding is in 90 degree plus temps (South Texas). It currently has a 85mm nozzle on it but I have an 87 I can change at will, just haven't tried it yet.
03-23-2008, 05:37 PM #7
Yes, you need to pitch up. Especially considering you are currently using an 85 nozzle, you can gain rpm's back by going to an 87. Like was said, 7150-7200 is the sweet spot.
03-23-2008, 05:53 PM #8
So how big of a jump should I do? Its currently 15/24, should I go 15/25 or 26?
03-23-2008, 08:42 PM #9
25 is about max on the DF before you go into point of no return. 26 will bring your rpms down but not much improvement in speed, your paralleling the root at this point. TJ's porting likes to run in the 7300s.
03-23-2008, 08:46 PM #10
You need to get with Lance. He and Fercho set the motor up and Lance likes to build buzz bombs. Plus when it gets hot, that prop is probably going to be just right.
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By rdewalt in forum 4-Tec PerformanceReplies: 4Last Post: 07-05-2009, 12:07 AM
By Turbo Todd in forum 4-Tec PerformanceReplies: 10Last Post: 11-21-2008, 10:55 AM
By Chrisrokc in forum Yamaha PWC Performance (2-stroke)Replies: 25Last Post: 07-17-2007, 05:45 PM
By Vern in forum 4-Tec PerformanceReplies: 21Last Post: 02-10-2007, 11:35 PM
By Jrsrxp in forum 4-Tec PerformanceReplies: 3Last Post: 05-17-2005, 02:50 PM