19 40 gears and 70 link chain?????

[Rx1M5]

Can I use a 70 link chain for 19 40 gears or do I need a 68?
Thanks

 

[Thatspec]

I believe anything lower than 20/40 would require the 68. Thats getting pretty low, are you also using a 3.0 pitch track with 7 tooth drivers?

Not to highjack your thread but along the same lines would 7 tooth 3.0 pitch drivers be lower gearing than 8 tooth 2.52 pitch?

MT

 

[Trxster]

I have been riding 20/42 which is the same 2.1 ratio but I am using stock 8 tooth drivers 2.5 pitch. I would say it is great for most everything but especially good for deep snow and trees. Not great if your racing on trails.

Rt

 

[Thatspec]

I wish I knew what my gearing was but suspect it is too high. Not about to break open the chaincase to find out. It does have 8 tooth 2.5p extroverts (I guess 8 is stock anyway) but will still hit 100 on the way up to the real snow. The original owner put a reverse kit on (changes forward gearing as well) but Hartman tells me there were two kits available with one geared more for east coast use (more like 22/38 ). Gears 'aint cheap not to mention the pita. Says this is likely why I have blown up two belts recently while boondocking/climbing.

Did a little searching but still can't find the definitive minimum for the switchover to a 68 link, sorry.

Damned if it isn't raining again here at 4000' in Oregon.

MT

 

[Trxster]

http://www.mountainperformance.com/yama ... _chain.htm

 

[Thrusted Vector]

The mountain RX stock is 21 40,reverse or not.The Apex is running 20 40

 

[Rx1M5]

I am going to try 19 40 with my 8 tooth 3.0 pitch drivers= 9 tooth 2.52. Currently I am running 19 42 which is pretty good all around.

I picked up a reverse for the sled which has a 40 tooth bottom so if I don't like this I can go 18 top or get the mpi 42 bottom for reverse. I was just wondering if I needed to order a new chain.

 

[Thrusted Vector]

Yup,a 68 tooth will be in order if you go with with 19 40

 

[Thatspec]

Any reason you can't use whatever size bottom (or top for that matter) gear you want with a reverse kit, or are they special with the reverse kit. This link;

http://www.yamahasportsplaza.com/pages/ ... fault.aspx

shows the kit being sold with either an 18/38, or 18/39, both pretty low gearing. I'd be happy if I had either of these but suspect not with the top end trail speeds I'm getting.

RX1M5, you say you have a 40 tooth compatible with reverse?

Thanks, Mark

 

[Thatspec]

I guess that link doesn't take you straight there. Have to plug in the '03 RX1 MT and click on reverse kit....

 

[Thrusted Vector]

40 tooth comes stock on the mtn reverse kit

 

[Rx1M5]

Yep thats correct

 

[Thatspec]

Here is/was one for sale with a 21/39 though perhaps this would not work on a MT;
http://www.ty4stroke.com/viewtopic.php? ... everse+kit

Appears either these kits were sold with a variety of gearing and /or.... any forward gears can be used???

Still curious, Any reason you can't use whatever size bottom (or top for that matter) gear you want with a mountain reverse kit, or are the forward gears specially made for the reverse kit only in certain sizes?

Thanks, Mark

 

[Thrusted Vector]

I f you get the kit cheap enough,you can swap out the 39 for a 40 easy enough or just the top gear to 20,however the difference between the 39-40 is fairly minimal.