did some testing today!

[snowbeast]

Thanks Pete,

I'm going to call him tonight.

My brother is going to Willard Mountain, NY tomorrow night. They are having 660' drags under the lights.

The first 100 feet is flat, and then you transition uphill, on a groomed surface.

He loves this set up. For him it works. I'll tell him about the xs811 belt.

Thought you were going to Patten? Ha, maybe you are there!

Thanks again,

I was but i have been fighting this darn broncitous thing,its all settling in my lungs,if i went out in the cold and start coughing,i cant stop,oh but stop me,where is the cold weather?? Well if he is going to a drag race that xs811 belt will most likely help him launch out of the hole,so how well is your snow holding up in eagle lake,and was it the plowed crossing where you guys are running bob. Thanks Pete

 

[hondo]

I called my brother, and he is going to try to pick one up.

He has a spot where he can try it out before he goes racing.

Yeah we were at the ice bridge, but need to make some longer runs.

We were running out of room.

The dreaded "Z's" don't come close anymore...LOL...

The last weekend he was here we went to Canada and raced the last 660' race. Conditions were very poor. He won 700 Improved.

Today it was 48 degrees. This snow is not going to last, especially after the pounding its going to get tomorrow.

Get well.

 

[snowbeast]

I called my brother, and he is going to try to pick one up.

He has a spot where he can try it out before he goes racing.

Yeah we were at the ice bridge, but need to make some longer runs.

We were running out of room.

The dreaded "Z's" don't come close anymore...LOL...

The last weekend he was here we went to Canada and raced the last 660' race. Conditions were very poor. He won 700 Improved.

Today it was 48 degrees. This snow is not going to last, especially after the pounding its going to get tomorrow.

Get well.

Good to hear he is going to do some r&d work for me lol,yea i thought your snow was going to start dissapearing soon bob,so what is the top speed you guys can muster between the old mill side of the lake and the other side on the island,maybe 120 speedo,is it still plowed,and is ice still semi hard??

 

[69redmach1]

1xr the smaller gear's will wear quicker because you are wraping the chain much tighter on the smaller gear and they need to run more rev to do the same job. you will put more hp to the groung with a 23/40 (1.73) than 22/38 (1.72) A 22/38 not only has to make a tighter curve around the gear but also has more curve around the tensioner. A 23/40 run's all together straighter, Less heat, Less resistance. I know the 40 bottom gear is not cheap but these chain cases get very hot when running high speed's for long distances. Also if you run out of gear these motor's will pull to the rev limiter (11,200) if cond's permit it. I am runing the 23/38 but have thought about going 23/40 many times. 99% of the cond's we ride in i would not use all of the 23/40 so i may as well have more mid range and top end in those condition's. kviper

My 22/38 chain is almost straight, very little tensioner. 23/38 you have to bury the tensioner with the 70 link chain. Since I own a chassis dyno/tuning shop we test gear ratios on cars all the time. A car with shorter(lower) rear gears will always show a little less hp on the dyno compared to higher geared cars to a point. The shorter geared cars are always faster, though, as long as it's within the powerband of the motor. All oem's over gear cars. That's the first upgrade recommendation I give customers, gear down!! There's 6 Yammi Apex's in our group now. On ice the 23-24 tooth sleds are faster than my 22 tooth. We rarely get to run on ice, though. On snow the 22 tooth is quicker all the way to the top, usually. I hit 113 on gps with my RTX so it will pull the gear past the charts. On a 1/4 mile ice strip I hit 107mph so I think the gearing is good for that too. It would be on a 1/2 mile or longer ice run that the GT's and Attack's would smoke me. We get those conditions only once a year or so. I've got a 70t chain and 23 tooth gear I bought to try and used one weekend if anyone's interested.
Pete

 

[hondo]

Hi Pete,

Three weeks ago my brother has seen 124 / 125 on the speedo, so I'm guessing real world 111 ish maybe 112. He ran out of room. He's guessing on a long run there is more, how much??? My brother said it was still pulling.

According to Danny at Rogers, on a long run perfect conditions, we should see close to between 128 - 134 on the speedo. So, if all things are equal that would mean 115 - 117 actual. Time will tell. Most likely next year.

Danny is Canadian, and races several sleds in the Canada 660' tour.

He has done very well in several classes this year.

Never-the-less I asked him about the overdrive machining.

What he did to my brothers sled and others, is at the base of the sheeves he has trimmed about .50 thousandth's off on each side.

According to Danny, What that does is: 1. makes the sheeve close closer together, and squeezes the belt tighter, so the belt rides up maybe an 1/8 of an inch. That enables the belt to ride higher on top, so 2. At top end the belt rides just a bit higher on the top of the sheeve. He claims very little power if any, is being robbed. It may be the difference of getting to the line first and preventing the other sled to drive by.

The sled turns between 10,500 and 10,800 rpms, which tells me there is a taller ratio. So 3. If you use a thicker, tackier belt all the better, and a bigger difference is noticed.

Rogers has been doing more and more performance mods., Nitrous kit installation, Superchargers, and Turbo Kits, along with machining, tracks etc... as previously mentioned.

When I was up there this morning I talked to a father, and son who drove 550 miles from Gansevoort, NY, to pick up the sons supercharged Apex. Danny installed a pop-off valve for them.

When you are riding up here sometime, stop into Roger's and say hello.

I know you have a lot of knowledge in this area, but it never hurts to see what someone else is doing, good or bad lol...

If my brother has any good results, I'll let you know.

Take care Pete,

Bob sends...

 

[snowbeast]

Thanks bob,are you still at camp in eagle lake or is that your year round house,i feel the same way mach69 feels the 22 helps 99% of the time,but i like the sounds of that belt to,anytime you can gear down and put more weight to your primary,pull your belt to the top of the sheaves,i feel you will go faster,at least in the right conditions.

 

[hondo]

Yeah Pete,

Year round.

I agree 69redmach1 made some good points.

It's the application. If your running on a long stretch of ice taller is better.

Getting a sled out of the hole and pulling in 660 - 1000 the 22 is probably a better choice, and with a little tweaking, can make it just a little better.

Tueday is going to be an interesting day.

I am meeting two Yam riders that are coming from Alaska. I believe these guys are going to shatter the Guiness Book of World Records, for the longest planned sled trip.

They are coming to Fort Kent for some work. My dealer said one was riding a Venture, and the other was riding an Attak. I'll be interested to pick their brains, and see how they did it.

If I find out anything good I'll send you a PM.

Take care,

 

[kviper]

69 red mach1, I agree with every thing you have posted so far but i think you mised my point. The 23/40 has basicaly the same ratio as the 22/38 but the bigger gear's will put more HP to the ground and run cooler as well. On my GT the 23/38 has a lot of wrap with the stock chain so with the 22/38 i would need a shorter chain. It would be a nobrainer for any one with anything but an 07 RTX (comes with 22/38) that want's to run the same ratio as the 22/38 to go to a 23/40. By the time you buy a 22 tooth top gear and a chain you may as well just buy the 40 bottom and have a better set up. kviper

 

[ReX]

69 red mach1, I agree with every thing you have posted so far but i think you mised my point. The 23/40 has basicaly the same ratio as the 22/38 but the bigger gear's will put more HP to the ground and run cooler as well. On my GT the 23/38 has a lot of wrap with the stock chain so with the 22/38 i would need a shorter chain. It would be a nobrainer for any one with anything but an 07 RTX (comes with 22/38) that want's to run the same ratio as the 22/38 to go to a 23/40. By the time you buy a 22 tooth top gear and a chain you may as well just buy the 40 bottom and have a better set up. kviper

Have you actually tested on a dyno or back to back speed runs the 22/38 vs 23/40?

The 23/40 has the disadvantage that the 40 takes up almost the entire outer perimeter of the case which means the oil has no where to go and would be worked much more. I agree that the larger radius upper gear would be more efficient, but I wonder how the extra working of the oil that a 40 lower causes plays into the big picture.

 

[kviper]

I personaly have not but srxspec,BBY and several other's have posted on this before. I am quite sure they have done testing with this setup. I am sure the gain's are very minimal as far as HP to the ground are concerned but in my case and any one else that already has a 23 top gear and want's the same ratio as the 22/38 it would only make sense. As far as the oil goes i would think it would be a non issue, At speed with the small amount of oil that is in the case there is probably not much oil left laying in the bottom. Also not only larger top gear but larger bottom as well and i would think it would run cooler. I am not here to argue so if you don't agree with this comon sense that is fine, It is your case, gear's and your money. kviper

 

[ReX]

I personaly have not but srxspec,BBY and several other's have posted on this before. I am quite sure they have done testing with this setup. I am sure the gain's are very minimal as far as HP to the ground are concerned but in my case and any one else that already has a 23 top gear and want's the same ratio as the 22/38 it would only make sense. As far as the oil goes i would think it would be a non issue, At speed with the small amount of oil that is in the case there is probably not much oil left laying in the bottom. Also not only larger top gear but larger bottom as well and i would think it would run cooler. I am not here to argue so if you don't agree with this comon sense that is fine, It is your case, gear's and your money. kviper

I'm sorry, but it isn't common sense to me that 23/40 has to be more efficient than 22/38. I'm a mechanical engineer and at university studied internal combustion engines, power transmission systems (including chain drives) and lubrication systems (including oil baths and pressurized lubrication systems). There can be huge losses in power when an oil bath is used if the oil is worked too much at higher rpms. Just look at the advantages to a dry sump engine and windage plates compared to old fashioned splash/bath lubrication systems.

Anyway, I genuinely would be interested in seeing a dyno comparison between 22/38 and 23/40 because I simply do not know which is more efficient and it is not obvious to me.