M1000 Clutching Idea's. trying to make sense of it.

[WyoBoy1000]

I put a lot of thought into this and it may not make sense as I tend to look at things differently than most, may have to read a couple times to put it together.

My 07 m1000 stock clutching worked much better than my 09 m1000 clutching and slp clutching, both sleds had slp pipe, the 07 would run 60mph track speed and on the flat would snap all the way to 95-97mph without a hiccup. the 09 might hit 50mph track speed and on the flat it snaps to 78-82mph and then slowly climbs and blows the belt. and at times it seems like off bottom it sling shots/ over engages the the clutching to far hits 7600 rpm and then binds and pulls the rpm down to 7200 and holds. It just so happens 78mph is when the clutching is at a 1:1 ratio, so each clutch has equal amount of surface area on the belt.

(the 07 had a for post which carried a lot more weight.)

this is what I found on the springs
on the parts list the 07 m1 uses a Y/W drive spring and a Orange driven
the 09 m1 comes with a purple and a orange. but also shows a option for the Y/W.

(Primary) the Y/W has a 122/285 rate(07) and the purple a 121/240 rate(09),

(Secondary) then the orange is a 175/280 rate.(both sled same)

Now it appears to me that with the purple spring and the required clutch weights to reach wanted rpm, it is not applying enough pressure to pull through the weight of the driven/orange spring (121/240 vs 175/285) causing the primary to slip and the secondary to bind. The 07 was 122/280 vs 175/285. I know the drive requires more tension to work and reduce slippage but it seems to be a ways off.

the 07 had a total of 272g of weight (68 each ) and the 09 225g(75g each)
so the 07 had 47g more to apply adequate pressure. any ideas on what would happen if I ran the same amount of weight on the 3 post and the Y/W primary spring.(or springs closer together in a sense, it would be a starting point) I know this is the route of my problem on the flat, as it quits working at a 1:1 ratio and the belts start to require different needs as it shifts into over drive. weather it be a softer driven spring or more force in the drive clutch. also the added weight might help slow down the sling shot effect enough to maintain rpm.

but I also want to run a 42/38 helix and a tension adjuster on the secondary and not sure how much it will change my needs.

parts list

07 M1000 4 post
SKU: 0646-229
Spring, Drive Clutch - Yellow/White
SKU: 0648-774
Spring, Driven Clutch - Orange

09 m1000
SKU: 0646-229
Spring, Drive Clutch - Yellow/White
SKU: 0646-155
Spring, Drive Clutch - Purple
SKU: 0648-774
Spring, Driven Clutch - Orange

 

[Woody67]

all year production M10s have had the yellow/white or ti version of the yellow/white. The purple is a low elevation 0-3K spring recommend from Cat.

it is interesting how a set up the same in almost every way except 4 post vs 3 post can run 30 grams more weight to acheive the same peak operating rpm

 

[DonoBBD]

Hands down I know your problem. I have seen this over and over. The primary on the three poster has a very very tight spring cup. Just like the secondary the spring needs to spin when compressed or the spring will belly. This bellying was fixed in the secondary with a shift assist. In the primary and the four poster there is more room in the spring cup and the spider shims were a bit different.

The fix is to cut more room for the spring in the spider cup. We have had them cut out to the edge of the roller tower. Then cut straight in. Then add two of the smallest friction washers you can find to pop in under the spring too that will act like a shift assist for the primary spring. You will still have to cut the OD of the shims so they can fit in this tight spring cup.

Look for paint warn off the OD of the primary spring and digs in the spider cup. IF you run the Ti spring once the paint is warn off it will stick and the spring will break.

Cheers Don.

 

[WyoBoy1000]

good info there, but still wondering what would happen if I throw 85-90g weights in.

 

[bgreen776]

Hands down I know your problem. I have seen this over and over. The primary on the three poster has a very very tight spring cup. Just like the secondary the spring needs to spin when compressed or the spring will belly. This bellying was fixed in the secondary with a shift assist. In the primary and the four poster there is more room in the spring cup and the spider shims were a bit different.

The fix is to cut more room for the spring in the spider cup. We have had them cut out to the edge of the roller tower. Then cut straight in. Then add two of the smallest friction washers you can find to pop in under the spring too that will act like a shift assist for the primary spring. You will still have to cut the OD of the shims so they can fit in this tight spring cup.

Look for paint warn off the OD of the primary spring and digs in the spider cup. IF you run the Ti spring once the paint is warn off it will stick and the spring will break.

Cheers Don.

Can you please post a picture of this?!!

 

[clutch]

The reason there is so much difference in weight, is that the heaviest part of a weight is the wide portion at the heel that the bolt goes through to hold it in the clutch. However, this part of the weight does absolutely nothing to make it shift, it simply holds it in the clutch. So having four weights adds a lot in that area that does nothing. Yes the 3 arm clutch needs heavier weights to compensate, but it is not an 1.25 ratio because of that. There is something else giving you a problem, and regardless of what Dono says grinding the spring cup out does not cure everything. I would also be very careful about grinding on the spider to cure that. The spider has a rough enough time not cracking and handling heat and horsepower without grinding it out and affecting balance and strength. Just my opinion of course, but be aware.

 

[Schags]

I might be wrong, but I heard it was just the Ti springs that had this trouble, could a different spring from cat, cutler, polaris fit without binding? Also, what Helix, and gears do you run in both sled?