Custom viper build

[mtndreamer]

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Due to ghost town situation on another site and the fact that I can't post pics for the 1000+ people that have looked at my build I am putting it over here for all you yamaha mountain 2-stroke junkies to view, add advice and help each other out.


I finally finished the skid today, good thing because we leave in just over 2 weeks, I am making a frankenstien here with 2010 arctic cat rails and a 2002 viper proaction skid, amazingly enough the mounting locations were pretty close and the extrusion was similar to the yamaha, many parts just crossed over, one big change was the mounting height for the front arm, to accomplish this height I had to turn the shock mounting bracket back 15 degrees to get it to the stock dimensions, instead of being 4 inches too high and having an approach angle that would just not work. I made my own transfer kit and had several other custom encounters but all in all it was not bad, maybe 12 hours, mainly R & D to make sure I was still ending up with yamaha dimensions. I will have to set the skid back as the cat rails are about 3" longer in the nose compared to stock yamaha. hopefully I can clear the steering hoop when I mount. I liked the look of the cat rails and plan to powdercoat them this summer if I like the set up. if not the proaction stuff is gone. next big step is getting this thing in the tunnel, i am currently porting the track so once this is done it will begin to go back together and look like a snowmobile. Thanks a gain for all the help and I will keep posting pics. we leave for the snowines on march 16th.

 

[snowdad4]

looking good. i bet you almost hate to get that skid in the snow! funny how the "change" elsewhere has affected so many. hope you have good snow for the big trip.

 

[deeperthebetter]

Nice work!!! Cant wait to see how well that all works out. 13 days and counting, til departure.

 

[BETHEVIPER]

I would mock that up with side plates with no springs first to make sure nothing is going to hit, like the front of your arms that look like they will hit the W arm.
When I do one of these remans, I use two pieces of plexiglass the size of the tunel, bolt the skid to it in the proper location, with track and drivers in it. Then you can compress each end and check clerences, bottoming stops, transfer gaps etc. That front arm worries me where it is located.

 

[..SNAKEBIT..]

welcome to the BEST DAM YAMAHA SITE ON THE WEB
the sw thing is starting to suck

 

[mtndreamer]

I would mock that up with side plates with no springs first to make sure nothing is going to hit, like the front of your arms that look like they will hit the W arm.
When I do one of these remans, I use two pieces of plexiglass the size of the tunel, bolt the skid to it in the proper location, with track and drivers in it. Then you can compress each end and check clerences, bottoming stops, transfer gaps etc. That front arm worries me where it is located.

thanks for the mock up idea, the arms would hit, but the shock will be bottomed out before that, have a 98 srx mountain skid that has no stops on it from the factory, guessing the shock is what stops it on that sled too?? the tip is a good one though.

 

[mtndreamer]

welcome to the BEST DAM YAMAHA SITE ON THE WEB
the sw thing is starting to suck

Snakebit, you had suggested to me to go with the holtzman attac system, which I purchased, beginning to install tonight and found my current jets at 150 in all 3 carbs, you were running 162.5,162.5,165 in your carbs, does it make sense for me to bump up? I already purchased the larger jets, the 150's is what this sled was setup for around here in iowa (don't know much since I put maybe 10 miles on sled before tearing into it (with this setup i had carbontech reeds, hauck husher pipes with stingers, and hauck clutching)) any ideas would be great

 

[BETHEVIPER]

on the jets, watch for venting in or out. Piped vipers have been set up both ways. It makes a huge difference on jetting.

Are you setting back your mounting hole? What drivers are you running? The rails look like they protrude too far in front of the front arm, unless your setting it back.

Another major point of interference is the FRA shaft. This normaly bottoms out the front of the skid against the bumpers that used to be on the lower section of W arm and against the flat plate mounted to the rails, close to the bottom of the rail. By the looks of the height of where the Warm is now located, if your rear arm and FRA is located at a stock length from the front Warm mount, it will hit way before the front shock bottoms out, limiting travel greatly.

 

[sideshowBob]

Nice job.
What did the suspension end up weighing?
If you post a request for jetting suggestions on the Viper/Srx forum someone will surely be able to provide a safe jetting spec. Include following details:
-type/brand of pipe
-ported?
-carb vents hooked up to airbox or hanging below carbs?
-the altitude and approx temp you wil be riding in?
-stock airbox or modified?

 

[mtndreamer]

on the jets, watch for venting in or out. Piped vipers have been set up both ways. It makes a huge difference on jetting.

Are you setting back your mounting hole? What drivers are you running? The rails look like they protrude too far in front of the front arm, unless your setting it back.

Another major point of interference is the FRA shaft. This normaly bottoms out the front of the skid against the bumpers that used to be on the lower section of W arm and against the flat plate mounted to the rails, close to the bottom of the rail. By the looks of the height of where the Warm is now located, if your rear arm and FRA is located at a stock length from the front Warm mount, it will hit way before the front shock bottoms out, limiting travel greatly.

I am setting it back, hopefully enough or less than the steering hoop dimesion, my srx mountain has no bottom plates to hit as a stop from the factory, it is obviously a 98 (since I think it was only made 1 year) i tried to mimick this factory setup, but i can see your point for sure, can you explain more in detail this FRA shaft and i will inspect further. Thanks for the suggestions. I am going out now to mount the skid.

 

[mtndreamer]

Nice job.
What did the suspension end up weighing?
If you post a request for jetting suggestions on the Viper/Srx forum someone will surely be able to provide a safe jetting spec. Include following details:
-type/brand of pipe
-ported?
-carb vents hooked up to airbox or hanging below carbs?
-the altitude and approx temp you wil be riding in?
-stock airbox or modified?

Thanks for the suggestion.

 

[gild]

MMax

Add MMax bump stops on the rails where the cross shaft of your W arm hits on the rails. Using the shock as a susp stop will cause damage to the shock as well as susp components. The MMax bump stops are quite high and can be trimmed somewhat for you to adj where bottoming the shock is not an issue. Good job though!!! Put a F7 front Fox Float in the rear and a SRX Ohlin front shock as your centre shock, works great!!!

 

[mtndreamer]

Add MMax bump stops on the rails where the cross shaft of your W arm hits on the rails. Using the shock as a susp stop will cause damage to the shock as well as susp components. The MMax bump stops are quite high and can be trimmed somewhat for you to adj where bottoming the shock is not an issue. Good job though!!! Put a F7 front Fox Float in the rear and a SRX Ohlin front shock as your centre shock, works great!!!

Anyone got pics of these bump stops?? appears that 2000 and older did not have bump stops as my 98 SRX, but I am wondering where they bottomed out at??? I have look at the SRX mountain skid twice now to make sure and I see nothing, looked on posts here of pre 2000 models and see no bump stops, and post 2000 have the h-arm with the stops high on the rail nose. I agreed that there needs to be something but we all know that the stops on the shorty viper with the w-arm don't work either, I have welded 3 of these, my w-arm can go almost to the rail tip as is, but the shock obviously limits it

 

[snowdad4]

my cat rails have the bump stop about 4" back from the rail tips. both my mtn max skids have them about 6" back, 00 and 01, same as the 03 mtn viper. my srx had a w arm and the bumps were pushed in the "v" of the arm and constantly broke off. all but the srx are just a riveted attachment to the rails. should show up in a microfishe somewhere, or i can drill some off and send them your way, as well as a pic from an 01 mm skid.

 

[mtndreamer]

my cat rails have the bump stop about 4" back from the rail tips. both my mtn max skids have them about 6" back, 00 and 01, same as the 03 mtn viper. my srx had a w arm and the bumps were pushed in the "v" of the arm and constantly broke off. all but the srx are just a riveted attachment to the rails. should show up in a microfishe somewhere, or i can drill some off and send them your way, as well as a pic from an 01 mm skid.

Drill some off snowdad?? don't you need em?? I have the stock stuff from the viper shorty, is that what you mean?? i don't think my w arm will touch the tips, maybe this is an issue, i will have to figure this one out, working on mounting skid currently, I will keep you all posted

 

[snowdad4]

emailed you some pics. i have 4 or 5 skids laying around from various yamahas, so if you want to add some, i have some and see no future need for them.

 

[mtndreamer]

emailed you some pics. i have 4 or 5 skids laying around from various yamahas, so if you want to add some, i have some and see no future need for them.

Okay, i will check the pics out in a minute, took skid apart because I believe in this site and the people who are interested in helping people out. the front of my w-arm is 1" off the top of the rail, and my shock bottoms out at 1.5" at the top of the rubber stopper (rubber not compressed, stopper on shock that is). so I am thinking those stops put in place at the front of the rail like you all are suggesting, especially snowdad, I figure the top of the rubber should be 2" off the rail so it has 1/2" + to compress, does this make sense to everyone?? I am glad this came up today because it has been in the back of my mind, just didn't want the stop set up like the viper had, too many woes from incorrect landings and rough trails in MN, and i definitely dont want to bend that lower shock mount either. SnowDAD I will pm you. thanks

 

[gild]

bump stops

The bump stops I mentioned are off of the 2000 and up " H " arm proaction suspensions. 141-144 inch long travel.

 

[mtndreamer]

The bump stops I mentioned are off of the 2000 and up " H " arm proaction suspensions. 141-144 inch long travel.

I think you and snowdad are on the same page, this will be the setup- thanks

 

[mtndreamer]

Skid is almost in, mock up pics

Got the w-arm placed in the tunnel it is 7 inches back and 3.5 inches up from the bottom of the cooler (makes it the same distance from the top of the tunnel as the stock mounting point). approach angle looks awesome, by the way the skid weighs in at 59 pounds, and my ported track is 42, what does a stock MM skid weigh?? I am still deciding on where the mounting holes will go for the rear scissor and drop bracket holes and the front shock mount/carrier axle. I have a good scissor to carrier number from my srx, looks like 15 7/8", i am going to search some threads and finish the skid install tom. night, then it is on to that seat, I have the seat frame built and the bracket it will attach to over the gas tank but need to play around with the mounting location for the monoshock, seat height is awesome and should look super clean when completed, any one know where to get a nice 4" LED light to mount under my seat???