Top end MPH on 17 SW.

[scottt]

The new version #2 B/O has more pressure on my drill press scale by quite a bit over V1. Tightening the secondary spring helps with top end slippage, raises RPM typically, and will backshift better.

The paper says the new version has a slightly different tang location compared to V1 so it has to be set at 6-2 on V2 to get the same torsion amount as the V1 spring set at 6-1. Has anyone tried the version 2 spring at 6-3 ?

 

[KnappAttack]

What are the characteristics if you go to far and put to much twist on the secondary spring

Thanks In advance

Reduced performance, hot belt and clutches. Same as too loose.

Too tight and it’s over pinching in the secondary, too loose and it’s slipping.

 

[KnappAttack]

The paper says the new version has a slightly different tang location compared to V1 so it has to be set at 6-2 on V2 to get the same torsion amount as the V1 spring set at 6-1. Has anyone tried the version 2 spring at 6-3 ?

I run 90 which is 6-3 on V2.

 

[scottt]

I run 90 which is 6-3 on V2.

You think that would be too much on my combo or ok to do?

 

[KnappAttack]

You think that would be too much on my combo or ok to do?

What is your combo? Power level? Helix, stock 8JP belt or 825 etc.

 

[scottt]

All stock except for TD power trail 250 hp SM flash,,b/o secondary spring, rollers and dalton primary weights. 8jp belt. I'm hoping the shop actually set the secondary spring at 6- 2 like the paper said and not 6-1.

 

[scottt]

All stock except for TD power trail 250 hp SM flash,,b/o secondary spring, rollers and dalton primary weights. 8jp belt. I'm hoping the shop actually set the secondary spring at 6- 2 like the paper said and not 6-1.

TTT

 

[Fast]

Thats just too light IMO on the B/O. I run 90 on the B/O with Hi-Torque rollers. On the big tunes 80 is not enough and will slip pretty bad.

People don't quite understand that the stock springs are near coil bind at the end and actually apply a lot of pressure at the top end. They are wimpy down low however. You need to wrap up the B/O tighter to provide the top end hold needed.

How hot is your secondary running that at 90, i tried that for 10 miles and thought the clutch was going to catch on fire

 

[KnappAttack]

How hot is your secondary running that at 90, i tried that for 10 miles and thought the clutch was going to catch on fire

Not hot at all, actually cool. What rollers are you running and how many miles on the rollers? Also what helix? What speeds are you running at?

 

[scottt]

I also noticed there are washers in between the helix and the clutch. I don't know if they were there when I bought it or after the shop installed the b/o spring and rollers.

 

[KnappAttack]

I also noticed there are washers in between the helix and the clutch. I don't know if they were there when I bought it or after the shop installed the b/o spring and rollers.

You don't need the washers under the helix if the primary isn't cut for OD. Some people did the washers because they thought, or were "told incorrectly" that the stock spring coil binds, which it comes close but does not actually coil bind at factory settings.

 

[scottt]

You don't need the washers under the helix if the primary isn't cut for OD. Some people did the washers because they thought, or were "told incorrectly" that the stock spring coil binds, which it comes close but does not actually coil bind at factory settings.

I dont believe the primary has been cut.Can the washers hurt top end mph? After I blew the belt (8jp) that was on the sled when I bought it I replaced it with another 8jp and now sometimes squeals when at operating temperature and idling.

 

[justinator]

I mentioned in another post on this topic but you need to adjust your beft deflection if your getting squealing at idle, your belt is a bit too tight. Remove a thin shim from behind the secondary mounting bolt and this should loosen your belt slightly and squeal will go away. It will have no effect on anything else.

 

[Fast]

Not hot at all, actually cool. What rollers are you running and how many miles on the rollers? Also what helix? What speeds are you running at?

14.5 rollers 35/39 reverse helix pink secondary spring at 6/3 runs 110gps in around 1000 feet with 1.5" track, with the black orange at 80 clutches were cool but rpm kept dropping on the top end could only get 105, maybe a straight 35 helix would work

 

[Clintww]

I'm running 33/35 with the B/O Seemed mine ran hotter at 6-3 than at 6-2 also during back to back tests. Stock tune with new rollers in both clutches.
RPMs are down a bit with the XS belt (8600), but I haven't tried any weight changes yet.