Power Kite Forum

thought i had 20s but they are only 15s!

turtlejoint - 30-5-2008 at 02:57 PM

I used to live in vegas so ivanpah was my buggy stomping grounds. I just moved to the beaches in northern california and my tires werent cutting it so I got a set of bigfoot rears from the pkf for sale section used for 150 plus shipping. they were a steal, already mounted on rims. turns out that i have the old xr buggy with 15 mm bolts instead of 20mm. bummer right? well the local machine shop is now forming a set of axle extensions that will make my axle a foot wider AND allow me to mount my bigfoots. Plus i can go back to skinny tires in about 5 minutes by just unscrewing them. its only going to cost me about 100 bucks. Ill post pics as soon as i get the buggy back from them next week.

i am so stoked!

USA_Eli_A - 30-5-2008 at 03:12 PM

yup, they 15s, but you keep em real clean

NPWfever - 30-5-2008 at 06:44 PM

Would it be possible to just add a spacer over the pre-existing bolt? That's what I did when I went from 1/2 to 3/4 inch on my buggy, I even used PVC, fit perfect, and lasted for like 6 months fine. Certainly a 12" length of steel tube would be cheaper than all that machining, like $3 versus $100. And would still let you switch back and forth easily, no mods.

kitemaker4 - 30-5-2008 at 07:57 PM

You are going to like the new wheels. It sure makes going through soft sand easy.

Susan (npw goddess)

USA_Eli_A - 31-5-2008 at 09:30 AM

there is a brass shim for converting 15mm-20mm,,,just head into a hardware store with your bolt. you might grab some shrink wrap, the extra 1mm the shrink wrap adds makes it nice and snug!

turtlejoint - 1-6-2008 at 08:58 PM

well i kind of wanted a wider axle too. so, im happy with this mod. and as far as wandering into the hardware store goes, its not quite that easy here. Im sort of in the boonies and metric fasteners arent readily available here. either way, this mod killed two birds with one stone and will really be a nifty one to see in action. but thanks for all of your suggestions regardless.

silvereaglekiter - 1-6-2008 at 09:19 PM

I had the same trouble with my new wheels No metric bushings at local hardware and none of my local machine shops wanted to make such a small order costume shim. I ended up ordering bronze bushings and new grade 8 bolts from www.mcmaster.com/ So what had been 3 months of headaches was solved in 5 min when the parts arrived
:thumbup:

turtlejoint - 1-6-2008 at 10:35 PM

out of curiosity, could you point me in the direction of those bushings? i couldnt find them on their site anywhere...

silvereaglekiter - 2-6-2008 at 06:12 AM

Sorry about that they list under Sleeve Bearings not bushings
Fallow Power Transmission > Sleeve Bearings > Sleeve Bearings > Flanged Sleeve Bearings

awindofchange - 2-6-2008 at 02:25 PM

We have 12 mm spacers and bearings in stock. The O.D. of the 12 and 15 mm bearing is identical, only the I.D. is changed so you should be able to pop out your 15's and put in 12's. The axle extensions sound pretty kewl, please post a picture of them when you get them finished. The 15mm axle bolts are a lot stronger anyways so you should be good. You may run into a problem with the 12mm threads on your extensions. With the added span of the rear axle you might put some serious stress on the 12mm section. I would make sure that you use a very strong thread to assemble the two together.

turtlejoint - 3-6-2008 at 10:23 AM

kent,

to be exact, the machine shop is making a 15mm to 3/4 SAE extension. it will have a 15mm male on one end to screw into the axle and a 3/4" SAE female on the other end to accept the Bigfoot tire. The extension will be 6in long on each side so the axle will be a foot wider. It might be done today or tomorrow hopefully.

funny thing is, i bought this buggy from your shop a few years ago and i could have sworn you said it was the xr+.

guess i should have brought my digital calipers.

popeyethewelder - 3-6-2008 at 01:31 PM

Quote:
Originally posted by kitemaker4
You are going to like the new wheels. It sure makes going through soft sand easy.

Susan (npw goddess)


You wait till you guys get the Euro Trax tyres, especially when fitted on asymmetric hubs, they are about 50mm taller than a full bigfoot on a cadkat....and loads wider too, soft sand is not even noticed...

the 15mm bolt/bearing is a right pain, 12mm bolts are too thin and bend far to easily, most larger buggy around Europe run on 20mm bolts

WELDNGOD - 3-6-2008 at 06:39 PM

how much ? American dollars! shipping?:wow: hey popeye I know this is OT but have you seen my blue baby?

0325081610a.jpg - 212kB

awindofchange - 4-6-2008 at 02:16 PM

Quote:
Originally posted by turtlejoint
kent,

to be exact, the machine shop is making a 15mm to 3/4 SAE extension. it will have a 15mm male on one end to screw into the axle and a 3/4" SAE female on the other end to accept the Bigfoot tire. The extension will be 6in long on each side so the axle will be a foot wider. It might be done today or tomorrow hopefully.

funny thing is, i bought this buggy from your shop a few years ago and i could have sworn you said it was the xr+.

guess i should have brought my digital calipers.


The Comp XR buggy had the 15mm bearings on the rear and 12mm on the front. The XR+ Buggy which was introduced about a year & 1/2 ago has the new 20mm bearings on the Rear and still uses the same 12mm bearings on the front. If your buggy has 15mm threads on the rear axle then it would be a Comp XR.

Still a much better buggy than the standard Comp buggy which has the 12mm bolts on the rear. With the 15mm rear axle you should be fine going to the 3/4" axle. Make sure to get us some pictures when your done because I have been interested in doing this same thing here. Would love to hear how it comes out.

turtlejoint - 4-6-2008 at 03:03 PM

well the machine shop was supposed to have it done yesterday.

i called down there and asked how it was going only to hear "Well, we havent even started on it yet..."

"ok, ill be there in 10 minutes to pick it up" was my reply...

i took it to another machine shop and they should have it done here soon. they are going to make it out of 4140 steel possibly stainless if the guy can find a couple spare chunks lying around. they are going to bore the existing axle to 3/4 in and continue with the rest as planned.

ill be sure to post pics once its done.

popeyethewelder - 10-6-2008 at 10:14 AM

Quote:
Originally posted by WELDNGOD
how much ? American dollars! shipping?:wow: hey popeye I know this is OT but have you seen my blue baby?


Yes WG, I have already seen it, you have had it a little while now havn't you

xxxBUGGYPILOTXXX - 10-6-2008 at 09:53 PM

Sand-Yeti - 23-6-2008 at 03:39 AM

Quote:
Originally posted by turtlejoint
I got a set of bigfoot rears for 150 plus shipping. turns out that i have the old xr buggy with 15 mm bolts instead of 20mm. bummer right? well the local machine shop is now forming a set of axle extensions that will make my axle a foot wider AND allow me to mount my bigfoots. Plus i can go back to skinny tires in about 5 minutes by just unscrewing them. its only going to cost me about 100 bucks. Ill post pics as soon as i get the buggy back from them next week.



This means your extensions stick out about 6" either side. I need to see pics of your mod.

PL used those awful non standard 15 mm fine metric threads simply because the standard inner diameter bearing size is 15 mm He had to go to 15mm because the 12mm axle bolts couldn't live with BF's.

We had problems even with the PL 15mm bolts. They would both break & bend from time to time.
Proper buggies have 20 mm axles bolts (standard thread) and a locknut between the axle & the wheel.
The later PL's have gone this 20mm route because of the known problems that were probably affecting their sales especially the earlier rubbish being built in China.

I would be afraid to use 6" long extensions on an axle screwed on at one end with a 15 mm thread. However, you could be OK if your terrain is easy riding.
Hopefully the local workshop has made good sized radii at the section change to reduce corner stress. If you make them from high quality tensile steel they could work well.

I bought some 15mm fine metric taps once to fix the PL bores in the PL axles that cost me an arm & a leg.

Rather than mess about making two long extensions, I think it would have been easier just to make a completey new rear axle for the length you desire with 20 mm tapped holes for the axle bolts.

I had the opposite problem to you with the PL split rims. The bearings in those are restricted by the outside diameter. I was unable to find bearings to fit them that had a 20 mm
inside diameter.
I made a new axle with 20 mm tapped holes in the end for fitting some wide offsets. However, I still wanted to make use of the old PL alu. split rims.
I machined stub shafts cut from a 20 mm high tensile bolt.
I have since sold that buggy with the PL alu. rims to one of my friends. He beats the hell out of the buggy and it's holding together very well.