Nyper build thread

[Nikolai]

Hi, I have been following for a long time but never got to posting...

For the idlers on my snowbike project I used some of the standard (around 5in) boggie wheel with a 6004 inside and cut the excess on the band saw then finished them on the lathe.... I guess this technique could work for your small lathe. Usually I turn an arbor the same size as the OD of the bearing and just press the wheel on the arbor.

On my project I could have built the wheels from scratch (14in lathe) but theses standard boggy wheel cost almost less than the piece of UHMW to make them

Keep on the good work! it is very inspiring

Awesome thanks. What wheels did you use? All of the bigger wheels I’ve seen that use a 6004 are skinny in the plastic portion if that makes sense. After you turned down them down the wider portion that hits the track would be gone and you’d be left riding on the narrow plastic that’s between the hub and outside. I’ve been looking at various wheels on Google trying to find something.

 

[fgauvin7]

Try to find some older Polaris indy or Yamaha wheel they are very chubby and have a lot more meat than the newer one

 

[Nikolai]

Appreciate the help, we have a snowmobile salvage not too far away, might go dig thru what they have.

 

[Nikolai]

I’ve always wanted some Titanium bolts. Absolutely a waste of money but I told myself I’d get a few for this build just because. I decided to get them for the chaincase, chaincase cover, speedo gear and brake caliper. The factory long chaincase bolts I think are 90mm in length, for my application they only need to be 85mm. All of the USA retailers only have 80mm and 90mm so I ordered from RaceTi in the UK. Excellent customer service, very quick to respond to emails and shipping only took about 2 weeks and was very reasonable. They were a lot less expensive than the USA sellers as well. Quality seems excellent and I’ll probably place another order for a few more. Can’t believe how light they feel in person.

Stock speedo gear and bolt, 60.96 grams

Counter bored speedo gear and Ti socket head bolt, 31.30 grams

Factory chaincase and cover bolts

Actually a pretty big difference, 0.33 lbs savings for just a few bolts plus they look good. These all have the dished heads, pictures just don’t show them.

Stock brake caliper

Unmodified Wilwood PS1 caliper

Bored some holes on the inside.

Bolted the two halves together and then ground the outside down to reduce weight but also increase clearance to the brake hub. Also counterbored the holes and bought shorter torx head Titanium bolts.

Modified caliper with Ti bolts. I also drilled out the M8 mounting holes and tapped them to M10x1.25 so I could use shorter M10 bolts without nuts protruding on the backside

Oilite bushing for the steering showed up today so I now have everything the finish up the steering post which I’ve been working on. Should have a good update on that in a couple days.

 

[kinger]

I am just trying to get my twincharged build running but assuming that works the way I want, my next phase will be light weight again and I love the chain case cover bolts! That is significant and I too want to go after a lot of un needed weight just like that. Looks amazing!

 

[Nikolai]

I wanted to get them for the front suspension but was worried about strength. From the reading Ive done Ti is suitable to replace 8.8 hardware and some 10.9 depending on application. My a-arms and shocks both use 8mm bolts so I ordered (8) M8-1.25x40 small head flange bolts (use 10mm wrench) and 8mm jet nuts, that was the lightest grade 10.9 hardware I could come up with. The lower front a-arm bolt is an M12-1.25x70(at least on my build) and rear lower a-arm bolt is an M10-1.25x60 so I might get Ti replacements for those along with 12mm nuts that retain the ball joint in the spindle.

I am going to order 8mm Ti bolts to replace the 4 bolts that hold the front motor mounts in place and also the starter and then probably call it good for the Ti.

 

[kinger]

You probably already know but use locktite in all Ti connections. The hardness of Ti makes it susceptible to harmonic vibration and can actually back itself out of rather high tq loads, fascinating really.

 

[Nikolai]

I did not know that. I had read that you wanted to use lubricant because Ti can have a tendency to gall threads and also adverse reactions to aluminum so when I put the brake caliper halves together I used medium strength loctite. I’ll make sure I loctite all the Ti bolts. Thanks for the tip.

 

[Nikolai]

Finished the upper a-arm jig today. Took longer than I thought to get it perfect but then so does everything about this sled.

Made bungs to fit inside 3/4 x .049 tube. Kept them as small as possible to minimize weight. Also ordered m12x1.25 half nuts to get rid of the wide factory jam nuts.

Doesn’t look like much but lots of hours into it.

The tube on the frame side that houses the bushings and sleeve will be 7/8 x .058 chromoly. The 2 main a-arm tubes will be 3/4 x .049 chromoly. The 7/8 tubes are 0.880” wide and there’s a .060” washer on each side to simulate a bushing flange(I will make UHMW bushings) for a total width of 1.00” which is what my a-arm and shock tabs are. I then made a 0.880” wide .762sh” OD steel bushing with 5/16 hole to fit inside the 7/8 tube for the jig. After that I turned the 7/8 tubes down to 0.879 so with everything clamped right the 7/8 tube can rotate so I can flip the a-arm over in the jig without loosening the bolts. Hope that makes sense. Should have the a-arms built in a few days.

There is a washer in between the bung and jig tab. I jig’d the factory a-arm that way so when I remove the 12mm bolt the washer will come out and allow clearance for the a-arm to swing up. Once I get the first a-arm fit and tacked I’ll flip it over and weld a tab on the other side of the jig to hold the bung. My goal was to be able to weld 90% of the a-arm in the jig.

 

[Nikolai]

 

[kinger]

Wow that’s light

 

[Nikolai]

Nytro Skinz front end w/ oem spindles, Ohlins shocks w/ Ti springs & all bolts was 27.21 lbs. That’s what I had on my sled when I weighed it at 449 dry years ago.

36” Sidewinder lower a-arms, my upper a-arms, oem spindles, Walker Evans air shocks & all bolts is right over 20.2 lbs. There’s a little guessing on the fat side because I need to make the upper a-arm bushings and some shock reducers but 20.2 should be real close or slightly on the heavy side.

My WE shocks need to be shortened from 17” to 16.34” for the 36” front end and I am going to look at installing Ti bolts while they are opened up (internal bolt is a grade 5 3/8-24x1.75). Also going to get Ti bolts & nuts for the lower a-arm only. I would like to get the complete front suspension under 20 lbs.

 

[Nikolai]

Upper a-arms 100% done.

Made UHMW and aluminum bushing setup. You will notice there is only a flange on one side of the bushings. When I welded up the a-arms and popped them out the jig the mounts moved toward each other. The a-arms have to be spread slightly to fit in the tabs(can spread by hand) so there was no need to have a flange on the outside. I’ve got a huge pile of scrap UHMW bushings, took awhile to figure out the correct process for making them. They push into the a-arm by hand with effort so they won’t turn inside the tube. The aluminum sleeves were all a slight push by hand so there’s absolutely no slop but also does not bind, very smooth thru range of motion. Glad this project is behind me.

Not bad for the a-arm with rod end and bushings.

M8-1.25 x 40 small head 10.9 bolts and class 10 metric K-nuts. A-arm and shock bolts all the same. Bolt & nut both use 10mm wrench.

Next project is to make 8 shock bearing reducers and shorten the shocks from 17” to 16.5”. Factory 36” front end shocks are 16.34” but I’m going to try 16.5” for the first test fit. I have Maxima light (3wt) shock oil on the way which is what was recommended to me by Fasttrax Motorsports who did the original rebuild on the shocks and has a lot of experience with the WE air shocks.

 

[Nikolai]

Had an extra 10mm anodized shaft I used for my spindle axles. Made the spacers out of my leftover 7075. I offset the skis inward to try and get the stance close to 35”. Each axle w/ spacers was only 0.12 lbs.

Got my clutch sheave back from @Thunder Products. Can’t say enough good about Terry, great service and price. 5mm was removed the back and 9mm of internal splines were removed.

My nitrogen needle adapter from Schmidty Racing arrived as well so I have everything I need to take apart the shocks.

Lots to do!

 

[74Nitro]

I drill a small hole to drain moisture from the ski saddle areas. I find that it greatly extends the life of the lower ski bushings and collars.
It also stops the runner/carbide hardware from rusting so soon.