Thread: Jetting Help Needed!!!
10-13-2006, 05:35 PM #1
- Join Date
- Jun 2006
Jetting Help Needed!!!
Hey guys I need some help. I usually hang out some on the Seadoo side but I now have a GPR also. I picked up a 2000 GPR 1200 that had a bad cylinder due to a lean condition I believe. Anyway, I putting a new stock motor in it (thanks shooter!!) and it has a R&D power plenum with the stock carb's & jetting. It also has a Riva pro series head with 41cc domes and jetworks mod. I think the lean condition was because of not rejetting with the addition of the R&D. Does anyone know what the jet specs. are for this type of set up. Thanks for any help, David
10-13-2006, 06:36 PM #2
what he's trying to say is what jetting will work with the R&D power plenum on a 2000 gpr 1200. It will have a high compression head as well, I think Dave said it was 150/155 lbs.
Well the Fercho jet specs work with the power plenum or will we have to jet a little higher to compensate for the extra air?
See you tomorrow Dave ya sap suckaaaaaa.
10-13-2006, 07:14 PM #3
1.5 Needle & Seat
Dull Grey spring 95 grams
120 main jets
Low speed screws 7/8
High speed screws 1 1/4 to 1 1/5
disable accellerator pump (use it for a primer)
This combo works with compression up to 150 with 92 octane gas
If you remove your choke plates go to 125 mains
Hope this helps. Fercho Developed it in 2001. I've been running it ever since
10-13-2006, 08:19 PM #4
- Join Date
- Apr 2006
- panama city beach 'fl
dave where you at ? temp.AND after failed did you rebuild carb's
10-13-2006, 09:21 PM #5
- Join Date
- Jun 2006
I'm in Augusta GA so it gets pretty warm & humid here in the summer. Mid 90's most of the summer when we ride. It does have a primer now & I believe the choke plates have been removed. We havent rebuilt the carbs yet because I just picked it up today. Thanks guys for your help! Shooter I'm going to be there probably about 3:00 or so.
10-14-2006, 06:03 AM #6
Chip, I am yanking the motor out and installing another motor in it that has 17 hours. I will be going through the carbs for him to double check everything. I wanted to check the jettings before we installed the power plenum back on it.
Thanks Spud and Kerry, I'll try and take some pics and post up this ski of his. Maybe if I get time, I'll post up my EFI boat.
10-16-2006, 02:31 PM #7
Shooter.....your such a good guy! Why didnt you tell me you were doing business with a fellow Georgian?
10-16-2006, 05:32 PM #8
Didn't know you were my daddy, sorry Tim, hahahahaha.
Why you want to come down and do some work? This **** is simple, the most time consuming thing is cleaning parts up. I am anal when it comes to it. As his power valves now sparkle, All I need to do now is put the stock head back on it, drop the motor in, check the jetting in the carbs, set it all back up for him and he should be good to go.
I told you before Tim, just bring your ski over and we'll fidget with it till we get it right. This stuff is simple, the hard part is the fine tuning.
Kerry, I ran the 110 lows and the 120 highs with a 2.3 n/s and a 80 gram spring with the riva flame arrestors. I had a bad bog on the bottom end, but the ski ran hard afterwards. I finally figured out what the problem was, but went to an EFI setup. The top of the pistons looked great and I had my high speed screws out at 1 1/4 turns on the front and middle and 1 1/4 + 1/8 turn on the rear.
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By ShakinSLX in forum Polaris Open DiscussionReplies: 3Last Post: 06-02-2013, 05:25 AM
By NJJer in forum Yamaha Old School SkisReplies: 27Last Post: 08-31-2009, 03:51 PM
By NJJer in forum Yamaha PWC Performance (2-stroke)Replies: 4Last Post: 08-28-2009, 08:31 PM
By Lvnspeed in forum Yamaha PWC Performance (2-stroke)Replies: 11Last Post: 08-25-2008, 11:59 AM
By xyzyx00 in forum Yamaha PWC Performance (2-stroke)Replies: 3Last Post: 08-29-2006, 05:57 PM