kinger
VIP Member
I hear ya! Mine are 5 and 8 now and finally getting some free time back! Now they want to 'help' me in the garage which just makes things go three times as slow. 
Nikolai
TY 4 Stroke God
One day I will have a small CNC plasma table. Until then, it’s the bandsaw and hand files.
4 shock & 8 a-arm tabs
Jigged & ready to weld
I was curious about the weight difference. My tube which has all 3 mounts built in
Factory shock mount only. No a-arm mounts or mounting bolts.
4 shock & 8 a-arm tabs
Jigged & ready to weld
I was curious about the weight difference. My tube which has all 3 mounts built in
Factory shock mount only. No a-arm mounts or mounting bolts.
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Nikolai
TY 4 Stroke God
I was researching steering post blocks a few weeks ago, trying to decide on a setup. I’m using a 1.125” post like the Pros use. The factory Pro plastic block is relatively light but wears out quick and can be sloppy. Most of the aftermarket options are significantly heavier.
I found an old post on Snowest by a member who is a big weight weenie, and ended up ordering the same setup after talking with him. Dealer called today and said parts were in.
It’s the aluminum strap from a Polaris IQR part #5132967, and the bushings from a 2010 Rush part #5437619. Total cost is about $35 and it’s extremely lightweight. Not to mention the bolts to mount it are significantly lighter(shorter) as well.
Factory Pro block with both aluminum sleeves in the ends.
36% lighter
I found an old post on Snowest by a member who is a big weight weenie, and ended up ordering the same setup after talking with him. Dealer called today and said parts were in.
It’s the aluminum strap from a Polaris IQR part #5132967, and the bushings from a 2010 Rush part #5437619. Total cost is about $35 and it’s extremely lightweight. Not to mention the bolts to mount it are significantly lighter(shorter) as well.
Factory Pro block with both aluminum sleeves in the ends.
36% lighter
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kinger
VIP Member
I love finds like that! What is the weight difference in lbs or oz?
Nikolai
TY 4 Stroke God
Stock Pro is 2.776 oz and IQR setup is 1.768 oz. so a 1.008 oz difference.
Got one a-arm/shock mount tacked and in place. It ended up in a slightly different position than I had pictured in my head. Going to have to modify my plan for the tube work a little.
Got one a-arm/shock mount tacked and in place. It ended up in a slightly different position than I had pictured in my head. Going to have to modify my plan for the tube work a little.
Mountainbilly90
Newbie
- Joined
- Jan 30, 2019
- Messages
- 7
- Age
- 34
- Location
- Rocky mountains
- Country
- USA
- Snowmobile
- 11 Phazer, 1982 bravo bunch of phazer 2s
Coming along nice!!! I'm more excited to see your build complete then I have been about yamahas release for the last 5 years lol. No intercooler on this setup?
Nikolai
TY 4 Stroke God
No intercooler, running a low boost kit.
Nikolai
TY 4 Stroke God
Made some progress and spent some time undoing some work as well. I spent today working on the front tubes which are .035. I’m using a mix of .035, .049 & .058 depending on what the tube is supporting. Trying my hardest to keep the weight down.
Started by welding the tops of the lower tubes since they’ll be covered by the upper tubes.
Got the Mag side front tube fit. I ran it as far into the steering mount as I could to get the largest welding area for support.
As soon as I got that tube in place I realized one of the a-arm tabs would be in the way. I want every tube on this chassis to be 100% fully welded so water cannot get in. I also will not be putting any holes in the tubes. When I cut apart my Nytro frame I had water and rust inside some of the tubes from putting rivets in them and a few weren’t fully welded. That was an eye opener and I don’t want this chassis rusting from the inside out.
So I had to grind the tack welds & remove the a-arm tab. Once I tack the tube in place, I’ll remove the a-arm tab(it’s just in place to help position the tube), weld the tube, then tack the a-arm tab back in place.
I also had to cut off part of the rear shock mount tabs as they’ll be in the way of the tubes that go down towards the rear.
Now that I’m done undoing work, I will fully weld what’s left of the shock mount tubes and bolt them in place, finish tack welding the front .035 tubes, then fit and tack the rear .049 tubes in place.
I know my posts are long but I’m hoping that they’ll save someone else some hassle if they decide to build a tube chassis.
Started by welding the tops of the lower tubes since they’ll be covered by the upper tubes.
Got the Mag side front tube fit. I ran it as far into the steering mount as I could to get the largest welding area for support.
As soon as I got that tube in place I realized one of the a-arm tabs would be in the way. I want every tube on this chassis to be 100% fully welded so water cannot get in. I also will not be putting any holes in the tubes. When I cut apart my Nytro frame I had water and rust inside some of the tubes from putting rivets in them and a few weren’t fully welded. That was an eye opener and I don’t want this chassis rusting from the inside out.
So I had to grind the tack welds & remove the a-arm tab. Once I tack the tube in place, I’ll remove the a-arm tab(it’s just in place to help position the tube), weld the tube, then tack the a-arm tab back in place.
I also had to cut off part of the rear shock mount tabs as they’ll be in the way of the tubes that go down towards the rear.
Now that I’m done undoing work, I will fully weld what’s left of the shock mount tubes and bolt them in place, finish tack welding the front .035 tubes, then fit and tack the rear .049 tubes in place.
I know my posts are long but I’m hoping that they’ll save someone else some hassle if they decide to build a tube chassis.
kennyspec
Expert
Awesome build! I also thought about having my tubie %100 welded so no rust could get in. I think the only spots are a couple screws for the seat and rivet for the flap. I siliconed every rivet when I installed it too. I’m not a big fan of doubling up the coolers. I think you would be better off with one larger cooler if possible.
I had mentioned I would detail my coolant system for you so here’s what I did. The material is from CR racing in BC Canada. Awesome material. Has fins on the inside as well. My cooler is 27” long x 4 passes. That’s it. No front cooler. I ride a lot of flat ground and hardpack and never had a issue with overheating.
I drilled through the tops with a 1” hole saw and then the coolant passes into that half round pipe. The pipe actually has bulkheads in it so the coolant has to go through all 4 runs of cooler in series.
I kept the tstat and my “bypass loop” is literally a hose from the front of that filler cap tube I built back to the tstat. The red cold light turns off in under a minute on warmup.
I have no expansion tank. Just that coolant filler cap setup. Never had it boil over and after a ride it’s not even that low. This tells me it can’t be getting too hot and I’m not loosing much coolant due to expansion and it having no where to go.
All hose fittings are from Ali express they were super cheap and work well.
Also something I found out, no matter how good your welds look your cooler is leaking. Pressure test it. I had so many tiny pinholes it was crazy. The best stuff I found to test with is that hand soap that comes out of the bottle in a aireated foam. Soap and water only seems to find the big ones. The aireated foam soap dispenser worked so so much better.
Nikolai
TY 4 Stroke God
Awesome, thanks for the writeup. My setup will be nearly identical. I won’t be on many trails so if you don’t have overheating issues than I know I won’t.
On the previous coolers I’ve built I used rubber hoses and a 30 psi gauge and pressurized the coolers to 15 psi. If the gauge drops I put the entire cooler in a bathtub full of water, the leaks show up instantly. And I agree, no matter how good the welds look I always have a few pinholes.
On the previous coolers I’ve built I used rubber hoses and a 30 psi gauge and pressurized the coolers to 15 psi. If the gauge drops I put the entire cooler in a bathtub full of water, the leaks show up instantly. And I agree, no matter how good the welds look I always have a few pinholes.
kennyspec
Expert
for your steering post I would do something like I did. I used the ball and round race from a nytro lower a arm where it connects to the spindle. put a 2 or 3" both through it and weld the head to the top of the ball. then find a tube that slips over the outer race of the ball and weld that to the steering shaft tube. would be a lot lighter than a universal setup and possibly smoother too. my steering setup is identical to that of the IQR direct steering setup yet it is on a pro rmk bulkhead.
Nikolai
TY 4 Stroke God
I looked at doing that as I have a bunch of extra Nytro ball joints but unless I’m missing something, I don’t see a way to do it on a direct steering post without messing up the geometry.
The factory Viper steering arm that the tie rods mount to is 90 degrees from the pivot tube. My u-joint would duplicate this(left drawing).
With a direct steering post, the rotation of the steering arm is around the post itself, so the steering arm would tilt up as it swings outside and raise the position of the inner rod end. As to what effect it would have the steering geometry I’m not totally sure.
My thinking is that while turning, the tie rod would be acting shorter(since it would be higher) and cause the skis to toe out.
I haven’t ordered the u-joint yet although I was going to on Monday, so I still have time to do something different.
The factory Viper steering arm that the tie rods mount to is 90 degrees from the pivot tube. My u-joint would duplicate this(left drawing).
With a direct steering post, the rotation of the steering arm is around the post itself, so the steering arm would tilt up as it swings outside and raise the position of the inner rod end. As to what effect it would have the steering geometry I’m not totally sure.
My thinking is that while turning, the tie rod would be acting shorter(since it would be higher) and cause the skis to toe out.
I haven’t ordered the u-joint yet although I was going to on Monday, so I still have time to do something different.
kennyspec
Expert
yes I agree it will be affected, by how much though probably not even a measurable amount. If this was a pavement F1 car I could see the geometry being the most important thing to consider, however 95% of your riding will be in off axis deep snow. Are you really going to notice your toe is out 1/32" as you are side hilling across a mountain? it seems as weight is your #1 consideration here so I would go for the lighter/ easier option using the ball joint. Either way it will work out awesome. wanna sell me your jig when your done ?!?!?!?!?
Nikolai
TY 4 Stroke God
Weight is the primary goal but handling is a very close second. If I knew I could do a straight post without any adverse handling affects then I would. I could mock up a straight post and see how much it raises the rod end, then I’d know for sure.
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Nikolai
TY 4 Stroke God
Finished the upper tubes. Welds are slowly starting to improve.
Got the front .035 tubes fit and tacked in place.
Started on the rear upright tubes which are .049. Pic is a rough idea of where it’ll end up. My plan was to tie them in further back with the other tubes(at the bottom) but the clutch side is unable to do that and they need to be the same left & right so my motor mount tube will be straight. Hopefully I can get these fit and tacked in the next couple days.
Got the front .035 tubes fit and tacked in place.
Started on the rear upright tubes which are .049. Pic is a rough idea of where it’ll end up. My plan was to tie them in further back with the other tubes(at the bottom) but the clutch side is unable to do that and they need to be the same left & right so my motor mount tube will be straight. Hopefully I can get these fit and tacked in the next couple days.
