2017 - Model 285 Restoration and Upgrade

[Slackjumper]

4/110 front hubs with 7" wheels

I really wanted more options for front tires and a bit more ground clearance. So, I picked up some polaris scrambler 90 front hubs, wheels and tires off ebay. Ordered 6202-10-2RS (6202-5/8-2RS) bearings to convert them to a 5/8 spindle. I probably could have used the standard 5/8x1-3/8 bearings but these 35mm OD bearings fit the polaris hubs perfectly. There is no need to turn the hub to fit these for the outer bearing if you are willing to give up the outer seal (both seals OD are ~35mm), you would need to get a longer bearing inner spacer also, but I wanted to reuse the stock spacer and keep both seals, so I opted to turn the hub on a lathe.

 

[Slackjumper]

Spacers for 4/110 polaris hub on 5/8

Turned the hub spacers from 5/8 ID 1"OD tube stock. The inner is 1" long and outer is 0.5" long, total length.

 

[Slackjumper]

Got the steering column support reconfigured and the skid plate too. The front two bolts for the seat go through the skip plate so I used 1/8" tread steel. I had to remove the 1/16 sheet steel under and behind the seat so it sits lower for bigger kids. Needs a new 1/8 strip to catch the back two seat bolts.

 

[Slackjumper]

Fuel tank mount

Figured out where the tank is going. Nowhere; darn solid. Bracket made from two briggs tank brackets that came with the frame. It's ugly but it'll be powder coated and hidden in a small gap between the tank and the seat back.

 

[Slackjumper]

Tank bracket back

Nuther pic

 

[Slackjumper]

Rear disc brake hub

Finished making the hub for the polaris rear disc. I started with the old band brake hub by cutting off the drum and lathing down the collar and welding the keyway into it on both ends.

I then lathed a piece of 3/8 steel donut for a 4" OD to press fit the ID onto the old collar, then weld. I made an alignment ledge on it that fits the disc's 2" center hole so that bolt hole play doesn't matter. It helped me get the holes drilled perfectly too. I put a 1/4" set screw through the keyway which seems to keep the assembly perpendicular to the axle darn well (very little disc wobble). Added two more set screws for good measure.

 

[Slackjumper]

Rear caliper mounted

Got the rear caliper mounted with 1/2" plate steel and 10mm fine thread bolts. Working good!

 

[Slackjumper]

Motor mounted

Motor mounted. Looks good!

 

[Slackjumper]

Trailer hitch

Also put a vertical pivot trailer hitch. I plan to weld a standard 1/2" shank mower horizontal pivot bracket to a short section of tubing with 4 skateboard bearings in it for vertical pivot.

 

[Slackjumper]

Steering wheel upgrade

Used leftover 1/8" tread steel to make a new steering wheel mount plate.

 

[Slackjumper]

Finally finished!!
I opted for a white powder coat.

I also lowered the TAV2 drive pulley engagement to 1800RPM with pink springs (PN 011186A). Doing that made this thing accelerate way the faster. (Chirps on concrete!) I had a hunch the stock springs are optimized for 5HP; and with the torque of my 8HP, the zinc weights can engage sooner with similar belt-slip to stock springs w/ 5HP. I'll be putting this 30 series TAV2 to the test this summer and update this thread later, but so far it hauls me (185lb) up very steep hills with ease.

Top speed is maybe 40mph, but I have yet to measure it. KYP

 

[Ebrownie]

That looks awesome. Looks like you did a good job getting in back in running condition.

I was driving around the other day on a back road and saw this guys yard with a bunch of crap in it, but there was an old Honda xr so I pulled in to his driveway out of curiousity. It ended up being a xr600 (way too big for me), so I lost interest in that, but there was also a good looking dingo frame sitting around the corner in his yard. The guy who owned the place wasn't there, but I am thinking about going back and offering him 50 bucks for it. I haven't found too many dingo frames in our area. Although, I really don't need another project at the moment... we'll see

 

[Hellion]

Only a fool passes up a Dingo.


Good job on the finish, Slackjumper.

 

[Slackjumper]

... but there was also a good looking dingo frame sitting around the corner in his yard. The guy who owned the place wasn't there, but I am thinking about going back and offering him 50 bucks for it. I haven't found too many dingo frames in our area. Although, I really don't need another project at the moment... we'll see

You should get it! They can be hard to find, & $50 is a steal. I got a model 388 the other day from my inlaws neighbor. $100 in good condition minus engine. I'll be putting the Honda GX390 on that later this summer.

 

[Slackjumper]

Ok I've already managed to burn up the 30 series belt. Looks like I need to upgrade to the 40 series. Does anyone know if the knock-off Ebay version like Auto-Express are any good? Saw a kit for $140 includes both pulleys. Are these the same as what the $370 40-series plate kit from GoPowerSports uses?

 

[Bubba_Z]

Slack, you get what you pay for. Yes you can get a cheap knock off but for all the work and soul you have put into this. Consider a Comet.
http://www.mfgsupply.com/gomini/gominiclutch/gominiclutchtorq.html
More money...yep
More work...yep
Better clutch....YEP
Remember, a 40 is NOT a 30. it is a completely different design.
I have over 2 hrs on mine at 27+hp and it is just starting to show signs of ware.
https://www.youtube.com/user/HTHCLLC/videos?sort=dd&view=0&shelf_id=0
Sorry I just dont agree that a 40 can run the driven "outboard" like you are forced to with a plate.

 

[RobertD]

By request of Slackjumper, moved to build off! Woot! He missed the memo when he started, but I'd say this looks like a pretty good entry that was documented. He loses points for reading the rules, , but looks like a nice build. Thanks for sharing with us Slackjumper!

 

[Slackjumper]

lesson learned: do not order torq converters from Auto Express. Poor shaft tolerances and poor customer service. They sent the wrong part and wouldn't pay for return shipping. After three email exchanges they are now ignoring me. Gokartsupply.com has been great however!

 

[Hellion]

Too bad you didn't listen to Bubba Z.

You did ask us though, which was wise. That's my modus operandi.

This was a Chinese knock-off with the poor shaft tolerances? Are the shafts egg shaped instead of round?
Do tell.

Guess this Auto Express is out of business because some casual (but effective) google-fu brought up nothing...?

 

[Slackjumper]

Comet 40 jackshaft done.

I finally got around to fabbing the jackshaft bracket. The motor sits on a 1/4" steel plate for a low center of gravity. Cut 3 large holes in the center to save some mass. I used a 16" 5/8 jackshaft in a 9.5" sch-80 pipe with four standard 499502H bearings. Outer bearings are snap-ring version. It seems to work fine up on jack stands. I look forward to testing it tomorrow.