Yerf Dog Front Tire Upgrade

[Rarerat]

I have been pestering everyone on the board for advice about which tires & rims to go with long enough, I ordered a set of Duro Thrasher 20x7x8 tires & 8x6 4on4 wheels for the front. Now I am just waiting on buster brown to deliver the new hubs and I should be able to rap this upgrade up. i got the tires yesterday and the wheels came in today, so I went out and mounted them up. My daughter is very excited to go try it out once the swap is done, and I have a feeling they will make quite a difference in the deep sand where we normally ride.






They are almost comical setting next to the stock wheels & tires.



They even make the rears looks small




Hopefully the hubs will get here tomorrow so we can wrap this up. I also bought a used pair of Honda TRX 250 Quad rear shocks that are 15"s long to try in the rear, but they haven't come in yet.

Hopefully it wont be overkill & will all work well together.

[SilverDuck]

Will those monsters turn without hitting the frame?

[Rarerat]

Originally Posted by SilverDuck

Will those monsters turn without hitting the frame?

That is yet to be determined.

I think so... I mean hope so.

[BuggyMaster]

Going to be a great upgrade. Don't worry about the backs being smaller, really not that uncommon.

[SilverDuck]

Keep me posted. If it works, I'll be the first to copy-cat you. Looks AWESOME.

[ckau]

you will be amazed at the difference these tires and wheels will make. The ride and steering response is fantastic compared to the stockers. I use a kenda front max with the same basic tread pattern. They work well in any type of terrain. Only problem now, your gonna want to upgrade the rear as well. A 22x7x10 is a good rear size to compliment the front. The 22's will give you better top end without loosing torque. I use the the Kenda XRC sport on the rear. The V pattern knobbys are bi directional. run them in one direction for soft/loose surfaces, V pointed forwards. or reverse them for harder terrain with a smoother ride. Orientate the tires on the wheels so all you have to do is swap sides on the rear to change pattern direction.

[SilverDuck]

Post a link to the hubs, wheels, and tires. I so am going to copy you.

[Rarerat]

Originally Posted by BuggyMaster

Going to be a great upgrade. Don't worry about the backs being smaller, really not that uncommon.

Originally Posted by SilverDuck

Keep me posted. If it works, I'll be the first to copy-cat you. Looks AWESOME.

Originally Posted by ckau

you will be amazed at the difference these tires and wheels will make. The ride and steering response is fantastic compared to the stockers. I use a kenda front max with the same basic tread pattern. They work well in any type of terrain. Only problem now, your gonna want to upgrade the rear as well. A 22x7x10 is a good rear size to compliment the front. The 22's will give you better top end without loosing torque. I use the the Kenda XRC sport on the rear. The V pattern knobbys are bi directional. run them in one direction for soft/loose surfaces, V pointed forwards. or reverse them for harder terrain with a smoother ride. Orientate the tires on the wheels so all you have to do is swap sides on the rear to change pattern direction.

Thanks guys.

I like the 22x7x10 rear tire idea and may go that route when the time comes. My daughter is really excited to get out there and try it out but per the tracking the hubs wont be here until Wednesday of this week.

Silver,
I'll keep you informed as I go.

[olderthan]

looks good
rears next

[Rarerat]

Originally Posted by SilverDuck

Post a link to the hubs, wheels, and tires. I so am going to copy you.

Here you go. Let me get the hubs in and get the tires on before you order anything, that way you will know 100% if they will clear or not. There is a possibility they might rub a little when you turn really tight, but I have a plan in place to solve that should it be the case.

I bought the wheels on ebay.

http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT

The tires came from Rocky Mountain....

http://www.rockymountainatvmc.com/pr...#vehicleSelect

And the hubs from BMI karts...
http://www.*************/shop/cart.php

[Rarerat]

Originally Posted by olderthan

looks good
rears next

Thanks

[metalstudman1]

Since I've modified the front steering and suspensions of the Spiderbox and my wife has put it through the beatings I'd like to add some food for thought. Unless you've upgraded the ball joints the bigger tires are going to wear them out REAL quick.The ride on your kart will be greatly improved as "ckau" says, also general stability will be better with the front end elavated. The biggest tire I could manage to put up front was 19" with out frame interferance and I extended my spindle shafts. I had also cut additional grooves in the rack for a better turning radius as the stock radius is terrible.I found thru trial and error that the tallest shock the kart could stand was 15" in the rear. Good luck with your mod's and big up's to you for making the effort.

[Rarerat]

Originally Posted by metalstudman1

Since I've modified the front steering and suspensions of the Spiderbox and my wife has put it through the beatings I'd like to add some food for thought. Unless you've upgraded the ball joints the bigger tires are going to wear them out REAL quick.The ride on your kart will be greatly improved as "ckau" says, also general stability will be better with the front end elavated. The biggest tire I could manage to put up front was 19" with out frame interferance and I extended my spindle shafts. I had also cut additional grooves in the rack for a better turning radius as the stock radius is terrible.I found thru trial and error that the tallest shock the kart could stand was 15" in the rear. Good luck with your mod's and big up's to you for making the effort.

Thanks, her buggy still has the stock ball joints and they are about shot as of now. I will need to replace them in the very near future. These are the rear shocks I bought on feebay to run on the rear.

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWNX%3AIT

I hope they will work well, but I didn't pay much for them so if they don't it's not a huge loss.

Can you explain your rack mods in a little more detail? i haven't really had time tinker with it, but it does appear to turn the tires unevenly for some reason. Her turning radius is terrible on that buggy and I was really hoping the new more aggressive tire would help tighten that up. Any advice you could give would be greatly appreciated.

Nick

[olderthan]

add shackles to the top shock mounts
your new shocks are longer than stock

[metalstudman1]

The shocks will work as the ones I'm using are from a TRX200SX.Do you have patience?Cutting 2 more grooves per side on the rack changes everything! Be very careful to cut the grooves the same spacing and depth (take your time) I did it with a 4" grinder w/ a cutting disk and cleaned it up with a file. I think the uneven turning of the wheels you're referring too is the Ackerman affect where the inside tire turns sharper than the outside one and is normal.The larger front tires will help eliminate scrubbing due to your tread design and elevated front end. I don't know if Tom sells the lifetime balljoints but ********** does.If this doesn't help let me know and I'll try to make a video.

[Rarerat]

Originally Posted by olderthan

add shackles to the top shock mounts
your new shocks are longer than stock

I am hoping the longer shocks will give it a bit more ground clearance.

Originally Posted by metalstudman1

The shocks will work as the ones I'm using are from a TRX200SX.Do you have patience?Cutting 2 more grooves per side on the rack changes everything! Be very careful to cut the grooves the same spacing and depth (take your time) I did it with a 4" grinder w/ a cutting disk and cleaned it up with a file. I think the uneven turning of the wheels you're referring too is the Ackerman affect where the inside tire turns sharper than the outside one and is normal.The larger front tires will help eliminate scrubbing due to your tread design and elevated front end. I don't know if Tom sells the lifetime balljoints but ********** does.If this doesn't help let me know and I'll try to make a video.

Thank you that does help.

[Rarerat]

****

[Rarerat]

Just an update on the tire upgrade. I finally received the hubs and got it all rapped up. They fit really well and although are very close on the right side do not rub. We couldn't be happier with the way it turned out and I would recommend this mod to all. I did enter this into the latest contest, hopefully it will qualify since it wasn't designed to be a direct bolt and took 3 suppliers to get it all to come together.

Anyway here is the end result.






Here a couple of pics with the wheels turned all the way. The left side has several inches of clearance, and the right side just clears by an 1/8 inch but does not rub.



I suspect once I replace to worn ball joints I may gain a little more clearance as the tires wont be leaning as much as they are now.

[olderthan]

i think it was well worth the effort
now for the new ball joints

[Rarerat]

Thanks, I will need to order the ball joints soon.

The new rear shocks came in today. These were a direct bolt with the only modification I had to do was cut and replace a few zip ties. The additional length of the shocks, leveled out the buggy real nice and they appear to be softer, & must have at least double the travel of the originals.

[olderthan]

i finally broke down and ordered blaster shocks
for the rear on mine

[BuggyMaster]

Wow what a difference that makes on the machine. Nice job! So, how's the ride and handling compared to stock?

[Rarerat]

The ride is quite a bit better with these shocks over the stock set up. But the difference in the way it handles is night & day. It doesn't even seem like the same buggy. Huge improvement!!

[ckau]

Originally Posted by Rarerat

The ride is quite a bit better with these shocks over the stock set up. But the difference in the way it handles is night & day. It doesn't even seem like the same buggy. Huge improvement!!

Yea! Good job. I knew you would like this mod. A buddy of mine tried my yerf after the conversion. His commit summed it up, " It drives like a car!"
Once you get the ball joint issues worked out, proper alignment set, the thrill goes up another notch! It's surprising how much horsepower, speed and handling is lost through a improper front end set up!

That difference in the turning radius and spacing between the tires and frame you mentioned is caused by bad ball joints and/or the rack and pinion not being centered. Disconnect the steering shaft from the rack. Remove the dust boots and manually move the rack to center. and look for a equal amount of teeth exposed on each side of the housing.Try your best to get the ball joints placed in the proper positions. Mark a point on the rims facing forwards. Measure the distance then rotate the rims 180 degrees towards the back , check the measurement. A folding carpenter rule with a sliding extension for inside measurement worked best for me rather than a floppy tape Adjust the steering rod length to give 1/8 inch toe out. Check the tooth positions constantly while taking measurements and adjusting. Position the steering wheel with the center spoke pointed down and reconnect it to the splined shaft.
The floppy ball joints can make this difficult at times and the alighment may not hold for long, again due to the joints but at least you will have the steering rack positioned correctly. Proper camber is impossible with the ball joints. there is no adjustment! your at the mercy of those stinkin things!
A tip.. once I got the correct alignment. I cut an old wooden broom handle to the proper length to act as a gauge. I check alignment by slipping the gauge in place between the rims. saves back and forth constant measuring.

[Tigger]

My front tires and rims are from the rear of a stock Polaris ATV and fit perfectly, the rims are 8 inches wide and have 5" offsets x 3" backspacing. the Tires are 22x11x10 this matches up well with my 22x11x8 on the back.

Tigger

[Rarerat]

Originally Posted by ckau

Yea! Good job. I knew you would like this mod. A buddy of mine tried my yerf after the conversion. His commit summed it up, " It drives like a car!"
Once you get the ball joint issues worked out, proper alignment set, the thrill goes up another notch! It's surprising how much horsepower, speed and handling is lost through a improper front end set up!

That difference in the turning radius and spacing between the tires and frame you mentioned is caused by bad ball joints and/or the rack and pinion not being centered. Disconnect the steering shaft from the rack. Remove the dust boots and manually move the rack to center. and look for a equal amount of teeth exposed on each side of the housing.Try your best to get the ball joints placed in the proper positions. Mark a point on the rims facing forwards. Measure the distance then rotate the rims 180 degrees towards the back , check the measurement. A folding carpenter rule with a sliding extension for inside measurement worked best for me rather than a floppy tape Adjust the steering rod length to give 1/8 inch toe out. Check the tooth positions constantly while taking measurements and adjusting. Position the steering wheel with the center spoke pointed down and reconnect it to the splined shaft.
The floppy ball joints can make this difficult at times and the alighment may not hold for long, again due to the joints but at least you will have the steering rack positioned correctly. Proper camber is impossible with the ball joints. there is no adjustment! your at the mercy of those stinkin things!
A tip.. once I got the correct alignment. I cut an old wooden broom handle to the proper length to act as a gauge. I check alignment by slipping the gauge in place between the rims. saves back and forth constant measuring.

Thanks for the great advice. After seeing your entry in the contest I think I will bag the new ball joints and follow your lead on the heim ends. Can I ask where you got yours? The last set I bought was from S&W race cars years ago for the ladder bars on my old Drag Car, but I haven't ever seen them this small. Did you just use a 3/8 joint & bolt on it?

[Rarerat]

Originally Posted by Tigger

My front tires and rims are from the rear of a stock Polaris ATV and fit perfectly, the rims are 8 inches wide and have 5" offsets x 3" backspacing. the Tires are 22x11x10 this matches up well with my 22x11x8 on the back.

Tigger

Nice job Tigger, and welcome to the crew.

[ckau]

Originally Posted by Rarerat

Thanks for the great advice. After seeing your entry in the contest I think I will bag the new ball joints and follow your lead on the heim ends. Can I ask where you got yours? The last set I bought was from S&W race cars years ago for the ladder bars on my old Drag Car, but I haven't ever seen them this small. Did you just use a 3/8 joint & bolt on it?

The heims came from American star. I found them, of all places, on Ebay!

[Rarerat]

I swapped out the new TRX 250 4 wheeler shocks I had recently installed on the rear of her Yerf for a set of 85 FL350R front shocks I had pulled from my 350 Odyssey. These lowered the rear of her buggy a touch from the 15" TRX shocks, but the ride vastly improved for her weight, and they are night and day better over the stock Yerf shocks. The handling seems to have improved as well with the addition of these shocks also.

[ckau]

one thing you need to watch for when adding longer shocks to the rear.
if the rear swing arm is not fairly level with the frame the motor is tilted to the point that the float level in the carb is upset. A out- of- wack fuel level will cause all sorts of problems. The best solutions are to either cut the shock brackets from the frame , flip them over, then reweld or or use the "mach brackets' for a no-weld fix. In the last pic the mounts were cut loose, rewelded higher on the frame to accomodate the longer shocks

[kliff]

"mach brackets," you got me on that one, explain please. when, where, how much....PM if necessary.

[ckau]

Mach brackets, named after a very clever and inovative man who first came up with the idea. He was known as Mach 1 on the now gone Yerfer net forum. you may be familar with him now as Guy48065. The first two pics in my previous post show versions of the Mach brackets, It's an excellent alternative if welding new brackets is not feasible.

[jetboy300]

Do you know who the distributor on Ebay was that you bought those wheels from? Does anybody know where I can get the 4x4 bolt pattern wheels to fit my front tires on? They need to be 8 inch diameter by 6 inch wide. Thanks, Roger

[Rarerat]

Originally Posted by jetboy300

Do you know who the distributor on Ebay was that you bought those wheels from? Does anybody know where I can get the 4x4 bolt pattern wheels to fit my front tires on? They need to be 8 inch diameter by 6 inch wide. Thanks, Roger

Check your PM's.

[xlint89]

Originally Posted by ckau

Adjust the steering rod length to give 1/8 inch toe out.

Are you sure you want 1/8" Toe Out? (front of tire measurement wider than rear of tire) I thought I read you wanted 1/8" - 1/4" Toe In???

Originally Posted by ckau

one thing you need to watch for when adding longer shocks to the rear.
if the rear swing arm is not fairly level with the frame the motor is tilted to the point that the float level in the carb is upset. A out- of- wack fuel level will cause all sorts of problems. The best solutions are to either cut the shock brackets from the frame , flip them over, then reweld or or use the "mach brackets' for a no-weld fix. In the last pic the mounts were cut loose, rewelded higher on the frame to accomodate the longer shocks

Thanks for this, I was wondering about that with the longer shocks.

[BSstatus]

alright im new to this website so bear with my here. do you guys think it would be a bad idea to put 4 25" tall tires on my yerf dog. or would it cut the torqe to much?

[x-bird]

25 is too tall for the rear for a 150. 22-23 max and then you'll want to have the cvt and gearing set for those.

[BSstatus]

alright I figured it would be. thanks

[jmansracerocket]

like x said, I use 22 inch on both of my buggies and like that size.