What do the numbers on contra/torque springs mean?

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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1man8scoots
CB900F
CB900F
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Joined: Wed Mar 18, 2015 11:49 am
Location: usa

Re: What do the numbers on contra/torque springs mean?

Post by 1man8scoots »

I have my 01 malossi iron shift or reblance at 9200, at which point when I hit 40 mph it descends to rest around 8500 by 50 as the ratios drop, and then begins to raise tach relative to land speed. This is how a cvt should work for max cruising speed relative to max engine power to the resting or cruising rpm. Flare ups shouldn't be your max power as they're only used for short bursts.
I know it seems like you should use the wot at cruising to get you into max hp, but you shouldn't be wot all the time and max hp should come as the cruising throttle position so you do not have to go wot. Those extra rpms when you go wot should be used for onset of hills or passing engine speed to get your variator to downshift and get the ratio into a position that would make use of the new engine speed and not the Max power to maintain.
Sounds like a loop of words I know but I hope it's easier for anyone to envision than explain.
Just remember it's a 49-81.25cc not a 350 cc twin so the tiniest adjustment of power can make or break the bike. I should have had hothatch85 ride the 01 elite before he left but I think my girlfriends stickers deterred him.
Rancher1
Spree
Spree
Posts: 113
Joined: Sun May 03, 2015 8:27 pm
Location: NorCal

Re: What do the numbers on contra/torque springs mean?

Post by Rancher1 »

I thought the Malossi iron doesn't make much power past 9k? In an ideal situation, don't you want to peg the shift RPM at the upper end but inside the power band (max HP)? I think what you're saying is it's better (though counterintuitive) to have the shift RPM higher than max HP RPM, and use partial throttle rather than WOT to create max HP RPM? I assume you're saying this from the practical perspective as us street riders don't WOT drag race off every red light.

What would be the bee's knees is an electronic programable CVT that actuates the front pulley based on your desired RPM profile.

I wish I knew someone in my area with a dyno.
1man8scoots
CB900F
CB900F
Posts: 1119
Joined: Wed Mar 18, 2015 11:49 am
Location: usa

Re: What do the numbers on contra/torque springs mean?

Post by 1man8scoots »

9200 is its end of the power band. Seat of the pants says 8500 is max power. You don't want it to over rev into no power but the end of its power band is perfect for changing lanes or take off to get your engine into an rpm it can handle when it settles. If you're drag racing you tune for max hp/rpm at wot and expect no dynamic shift in power through out the run.
Rancher1
Spree
Spree
Posts: 113
Joined: Sun May 03, 2015 8:27 pm
Location: NorCal

Re: What do the numbers on contra/torque springs mean?

Post by Rancher1 »

That makes sense. I did something similar but didn't know the RPM numbers. I tune to how it feels depending on the type of roads/usage. I lived in a place with a couple of long steep hills at speeds that pretty much needed WOT to stay with traffic, so the bike was tuned for max HP at WOT just for those hills. Another place was mostly city riding - low top speeds and lots of stop-and-go. It didn't need much extra HP but was tuned for more slower speed / lower-mid-end HP for max acceleration dodging clueless cars. Now I live in a place somewhere in-between those. Some slow city but mostly longer open roads that need some speed to stay with traffic. I suspect this bike's tune will be closer to what you described but with weights likely on the heavier side. Going for weights that let the bike comfortably cruise at partial throttle at the speeds I need.
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