sxr500 8000 shift rpm too high? UPDATE
I have a goodwin clutch kit in my sxr, worked great for trail riding and always pulled a steady 7800rpms until she topped out. I've been trying to get the sled to launch harder out of the hole, with the kit the primary engaged at 4500. With the 500's weak power in that range, I wanted a bit more pull out of the hole and added 2 shims to the primary spring (white). This upped engagement to 4700 (according to tach), and also upped my shift rpm about the same (100-200rpms). The sled accelerates awesome, pulls harder than ever, backshifts great, no complaints, other than the slightly high shift rpm. Question is, should I worry about the extra 200 rpms? I know the tachs arent always spot on, is there anything to worry about? I hardly ever do any lake running, aside from a short burst racing buddies across fields.
I have a goodwin clutch kit in my sxr, worked great for trail riding and always pulled a steady 7800rpms until she topped out. I've been trying to get the sled to launch harder out of the hole, with the kit the primary engaged at 4500. With the 500's weak power in that range, I wanted a bit more pull out of the hole and added 2 shims to the primary spring (white). This upped engagement to 4700 (according to tach), and also upped my shift rpm about the same (100-200rpms). The sled accelerates awesome, pulls harder than ever, backshifts great, no complaints, other than the slightly high shift rpm. Question is, should I worry about the extra 200 rpms? I know the tachs arent always spot on, is there anything to worry about? I hardly ever do any lake running, aside from a short burst racing buddies across fields.
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i would wait for turk to chime in but i think you need to add some weight to the tips. overreving does bad things to piston skirts and might cost you more in the long run.
nailsandrails
VIP Member
What is the secondary set at and what spring?
FuzzButt
New member
FWIW my 600 used to rev up thru 8200 until I got the weights right. Now I see 7800 and not much more even thru 90MPH. The twin makes the most power at 7800 so running it any faster will not result in more HP.
A higher engagement will also hurt your economy. So if your trail riding it might cost you a bit.
Personally if you are trying to overcome the 500's power band issues I would stick with Turk's and Vmax John's setup for the 500 on the bottom of the tech page.
I think if you want better out of the hole power a gear swap is in your future. Also maybe a different helix in the secondary.
A higher engagement will also hurt your economy. So if your trail riding it might cost you a bit.
Personally if you are trying to overcome the 500's power band issues I would stick with Turk's and Vmax John's setup for the 500 on the bottom of the tech page.
I think if you want better out of the hole power a gear swap is in your future. Also maybe a different helix in the secondary.
Went out in the garage to check things out further. The goodwin clutch kit came with a white primary spring with a 5mm aluminum spacer. engaged at 4200 when hit from idle and at 4500 when slowly revved to engagement. Wound at #3 on sheave, #0 on helix (30 degree's?), Helix stamped with 50/38, Black spring. 8DN belt. I went down 1 shim from the first post (now have 5mm goodwin shim and 1mm shim=6mm additional preload). Engagement at 4300 when hit from idle, 4600 when slowly revved. Shift rpm down to 7850 on hardpack, flirts with 8000 in powder. Still haven't checked out what it has installed for weights. The sled has improved greatly with the addition of the 1mm shim, and I also spent a bit more time dialing in jetting. Had to go out slightly on the fuel screws (at 2 turns now) and I may lean the needles half a groove as i'm getting a slight rich gurgle after riding for a bit and engine temps get up. gurgle is around 1/2-3/4 throttle. Plugs read ok, a darker cardboard brown with minimal carbon and oil, I think the needle change will clean it up further. I'm still flirting with the idea of dropping to a 20T on the top gear in the chaincase, as well as the reed notch mod.
I also found a rear heat exchanger out of a 700 sxr that I plan on installing to keep engine temps down. Has anyone installed stiffer springs on the 01 front shocks? I'm getting an awful lot of sag even with the springs preload turned up an additional 30mm over stock. My bellypan is working as more of a flotation device than my skis.
stock skis?
i know my stockers sucked in the powder, had to use the trhottle to keep it on top of the snow. i put on a set of viper skis and it helped. brother i sold it to has since put on phazer mountain skis and says it floats much better in the snow now.
i know my stockers sucked in the powder, had to use the trhottle to keep it on top of the snow. i put on a set of viper skis and it helped. brother i sold it to has since put on phazer mountain skis and says it floats much better in the snow now.