WNR18
New member
Sled is a 2000 SRX with 144 AC skid 144 1.5 inch lug
Current setup: 8DN-20 4.5 g inner/outer plus 0.8 g washer outer hole
Total: 52 grams
Spring:blue pink blue 66-211
Secondary: 45 helix with Yamaha pink spring 70-80 twist
Gearing: 23/40
Conditions: Deep snow/xcountry and trail
Performance: Start to 50-55 mph 8500rpm. Afterwards rpm climbs to 87-8800. Backshift is good especially when loaded hard.
Tried 47 helix. It will not pull it on the bottom. Rpm is okay on top. Backshift is poor.Tried a silver spring. Still over-reved, belt hotter. Do not like the idea of tuning rpm with helix/spring, loss of belt pinch.
I know I need more shift force on the top.
Thinking about giving 8BU-10 a try? Reading about 8BU-10. Lots of positive comments. I have not read any reports with longer tracks.
Parts on hand: All Yamaha secondary springs plus a cat green. All Yamaha helixs except 51-43, an unknown 50-44. G-P-G 66-266 primary spring.
I also have 22/40 gearing available. 100 mph is not my thing anymore. I want it to work good both on trail and off. Any thoughts grately appreciated.
Current setup: 8DN-20 4.5 g inner/outer plus 0.8 g washer outer hole
Total: 52 grams
Spring:blue pink blue 66-211
Secondary: 45 helix with Yamaha pink spring 70-80 twist
Gearing: 23/40
Conditions: Deep snow/xcountry and trail
Performance: Start to 50-55 mph 8500rpm. Afterwards rpm climbs to 87-8800. Backshift is good especially when loaded hard.
Tried 47 helix. It will not pull it on the bottom. Rpm is okay on top. Backshift is poor.Tried a silver spring. Still over-reved, belt hotter. Do not like the idea of tuning rpm with helix/spring, loss of belt pinch.
I know I need more shift force on the top.
Thinking about giving 8BU-10 a try? Reading about 8BU-10. Lots of positive comments. I have not read any reports with longer tracks.
Parts on hand: All Yamaha secondary springs plus a cat green. All Yamaha helixs except 51-43, an unknown 50-44. G-P-G 66-266 primary spring.
I also have 22/40 gearing available. 100 mph is not my thing anymore. I want it to work good both on trail and off. Any thoughts grately appreciated.
orchie18
Member
im not convinced that the 8bus 10 are an awsome all around weight. They work great on my 144 srx on hard pack but off trail they leave alot on the table. They are great for drag racing if set up right. Ive been switching back and forth between the 8dn and 8bu for a couple of years, our conditions vary so much that its a never ending battle to keep me happy in all conditions. If you can find a set give them a try. they do haul A** if setup right.
YAMMIEGOD3:16
Active member
8bu- 10 are the best weight yamaha has for pure top end speed. the 89a-10 are close second. 8bu-00 are the best weights yamaha has for racing/ best e.t.. with all this said, you have to fine the happy spot for a tuner thats wants all. probley why the 8dn-20 weights are very good. now tuneing for a 144 is a hole new animal, but i would try them. 3:16 (yammie tony)
Used heel clickers in my 780 144x2 sled. Mostly off trail/boon docking/mountain riding. Used them at 1200 and 8000 plus elevation. Pulled like a train and would still run 90 ish mph when necessary. I used a 50/38 and also ran a team roller with them. Dn-20's are decent off trail weight. Load them till it won't pull it anymore and then back them off. Sucks drilling/pounding rivets though figuring it out. That's how I ended up using the clickers. Had good results with both the 40-10 and the 2 speeds. My 2 pennies 
YAMMIEGOD3:16
Active member
great point, when all fails and your done smashing rivets, heel clickers. i agree. 3:16 (yammie tony)
WNR18
New member
THanks for the info.