Bikeman adjustable weights with MPI sea level

[Threeman03]

has anyone ever used the Bikeman 60-70 g adjustable weights with magnets in their sr viper with MPI turbo kit?
If so what set up did you find works best for weights?
Heel? Mid ? Toe ? Added weights amounts?

 

[shadow637]

I have just started to use these and have no real baseline yet. I have one magnet in each position and I am trying to figure out the best primary spring to go with.

 

[Threeman03]

I have just started to use these and have no real baseline yet. I have one magnet in each position and I am trying to figure out the best primary spring to go with.

I have zero magnets in now with 47 deg helix
And stock springs. I was thinking about adding 1 to heel and tip.

 

[shadow637]

I started with a B-S-B stock spring with 1 magnet in each position and it was under-reving pretty bad with horrible throttle response so I thru in a G-W-G and it was better but still low on rpm. My selection of Yamaha primary springs is a bit limited (ran Drag-n-Fly weights/springs in my Nytro for many years). Most of the Yamaha springs I have are from my SRX and OG Viper days so they are higher preload for 2-stroke engagement. I ended up throwing in a Super Torquer black spring for the hell of it and now I am hitting the limiter pretty bad. I think a Yamaha P-P-P spring might be a good starting spot.

I am currently running the stock pink sec spring @ 6-1 with a 54-45 helix.

 

[Studroes144]

I started with a B-S-B stock spring with 1 magnet in each position and it was under-reving pretty bad with horrible throttle response so I thru in a G-W-G and it was better but still low on rpm. My selection of Yamaha primary springs is a bit limited (ran Drag-n-Fly weights/springs in my Nytro for many years). Most of the Yamaha springs I have are from my SRX and OG Viper days so they are higher preload for 2-stroke engagement. I ended up throwing in a Super Torquer black spring for the hell of it and now I am hitting the limiter pretty bad. I think a Yamaha P-P-P spring might be a good starting spot.

I am currently running the stock pink sec spring @ 6-1 with a 54-45 helix.

54/45 seems extremely steep. I tried a 50/46 and 51/43 with my turbo last year, both of them just wanted to shift too quick and didn't have enough adjustment on the weights to make it work and rpm were always a bit low. Switched back to the stock 43 helix and it worked awesome, stock pink secondary spring at 6-2, whether on perfect hard packed or fresh deep snow it pulled 8800-9000 very consistently all the time.

 

[shadow637]

54/45 seems extremely steep. I tried a 50/46 and 51/43 with my turbo last year, both of them just wanted to shift too quick and didn't have enough adjustment on the weights to make it work and rpm were always a bit low. Switched back to the stock 43 helix and it worked awesome, stock pink secondary spring at 6-2, whether on perfect hard packed or fresh deep snow it pulled 8800-9000 very consistently all the time.

Thanks, I will give the stock helix a try. I also have a couple in between, just need time to do some quality testing.

 

[SRXracer]

I went to these last year after a Supertip weight broke in half on the trail. I was running them today - secondary exactly like Studroes144 said, OPO primary, and 3-3-1 for the magnets in the holes. I am still hitting the rev limiter once or twice at times on hard stabs on the throttle, but it's pretty close. 87-9000 rpms. I wish I could get a little more weight in the heel and middle - might have to go to a little more aggressive helix than the stock, or possibly gear up a bit.

 

[Threeman03]

I went to these last year after a Supertip weight broke in half on the trail. I was running them today - secondary exactly like Studroes144 said, OPO primary, and 3-3-1 for the magnets in the holes. I am still hitting the rev limiter once or twice at times on hard stabs on the throttle, but it's pretty close. 87-9000 rpms. I wish I could get a little more weight in the heel and middle - might have to go to a little more aggressive helix than the stock, or possibly gear up a bit.

Why would you not add 3 to the tip? If your hitting rev. The tip is where u should add weight ..right?

 

[Threeman03]

I'm
Going to try
2-0-2

 

[shadow637]

I went to these last year after a Supertip weight broke in half on the trail. I was running them today - secondary exactly like Studroes144 said, OPO primary, and 3-3-1 for the magnets in the holes. I am still hitting the rev limiter once or twice at times on hard stabs on the throttle, but it's pretty close. 87-9000 rpms. I wish I could get a little more weight in the heel and middle - might have to go to a little more aggressive helix than the stock, or possibly gear up a bit.

You could give the PPP spring a shot, it has a bit less rate then the OPO with the same preload. My thinking is- try to get the rpm close with the weights in the middle of their adj range and have room to fine tune either direction.

 

[SRXracer]

Why would you not add 3 to the tip? If your hitting rev. The tip is where u should add weight ..right?

It's not really over revving once the sled settles down and get's rolling. It's mostly right on the initial holeshot or throttle stab on a roll. Like 30-40 mph. The first hole effects that the most, and then the second. The tip has the greatest effect on the full shift rpm once at higher speeds/clutch shift ratios. At least that's what i've always understood.