Post by jacques on Mar 26, 2011 17:11:06 GMT
I've had a couple of folks ask how one goes about converting a 4 stud 'bowl' type front hub arrangement to the 5 stud primmy style design on a V range. Rather than respond in each instance I thought I'd put up a brief explanantion as to 'How'. Sorry it's a bit wordy but I don't have any 'as-you-go' photos.
The 4 stud design and 5 stud design share a few common elements such as the swingarm (traverse) assembly, bearings, bearing retaining rings, circlips & oil seals. The only items that differ is the axle & hub(s). You will also need a hub nut cover for the 5 stud design. With a bit of patience one can do the conversion in 30 mins.
Firstly, this is what the 4 stud looks like.
4 stud rim and hub assembly
drum and axle / flange
drum and axle
In order to go from 4 to 5 stud hubs, you need to remove the axle with flange from the traverse and replace it with a single axle to take the 5 stud hub. You will also need a 5 stud brake drum / hub.
Axle for 5 stud hub. image from the SIP website
Here's How-
1) Begin by removing the rim from the outer hub.
2) Remove the outer hub. You should now be left with the brake drum bowl.
3) Remove the little locator nib
4) You now have to gently pry the drake drum from the face of the flange. If yours is anything like mine and rusted solid you may need to spray it with some WD40 and let it soak for a bit.
In order to remove the flange and axle, you have to turn to the other side of the traverse
5) remove the rubber bung near the shock mounting.
6) remove the speedo pinion gear which is accessed via the big flat screw head.
7) remove the speedo drive gear under the rubber bung. (Reverse thread I believe)
7) using a drift & hammer, tap the axle out. It should pop out the other side.
8) you can now remove the oil seal, circlip on the brake drum side.
9) I had to tap the hub side bearing out using a drift and hammer, you have to tap them out from the opposite side.
If you are replacing the bearing it's best to do the following, otherwise skip to 12.
11) You have to remove the locking ring holding the inner bearing in place. I found the best way to do this is to place a screwdriver in the notch of the retaining ring and tap it out. The ring is left hand threaded so you have to tap it sideways to loosen. There is a special vespa tool but who needs them! ;D
12) extract last bearing using a drift.
To re-assemble, you do it all in reverse.
1) Replace inner bearing and pack the bearing out with grease, replace locking ring.
2) It's best to freeze the axle or heat the bearing a bit to make inserting the axle easier. replace the axle so that the grooved end faces the drake drum and the threaded bit goes toward the rubber bung.
3) replace outer bearing with some more grease, followed by circlip and oil seal.
4) turn over and replace drive gears. I found it easier to temporarily fit the new hhub to tighten the speedo gear as you can grip it better.
5)Pop in the rubber bung.
6) Fit the brake pads and little circlips
7) slot on your 5 stud hub / drum, pop on the washer and slotted nut and split pin
8) pop on your rims and off you go. ;D ;D
5 stud brake drum hub and two part rim.
Hope it's of some use to someone.
J
The 4 stud design and 5 stud design share a few common elements such as the swingarm (traverse) assembly, bearings, bearing retaining rings, circlips & oil seals. The only items that differ is the axle & hub(s). You will also need a hub nut cover for the 5 stud design. With a bit of patience one can do the conversion in 30 mins.
Firstly, this is what the 4 stud looks like.
4 stud rim and hub assembly
drum and axle / flange
drum and axle
In order to go from 4 to 5 stud hubs, you need to remove the axle with flange from the traverse and replace it with a single axle to take the 5 stud hub. You will also need a 5 stud brake drum / hub.
Axle for 5 stud hub. image from the SIP website
Here's How-
1) Begin by removing the rim from the outer hub.
2) Remove the outer hub. You should now be left with the brake drum bowl.
3) Remove the little locator nib
4) You now have to gently pry the drake drum from the face of the flange. If yours is anything like mine and rusted solid you may need to spray it with some WD40 and let it soak for a bit.
In order to remove the flange and axle, you have to turn to the other side of the traverse
5) remove the rubber bung near the shock mounting.
6) remove the speedo pinion gear which is accessed via the big flat screw head.
7) remove the speedo drive gear under the rubber bung. (Reverse thread I believe)
7) using a drift & hammer, tap the axle out. It should pop out the other side.
8) you can now remove the oil seal, circlip on the brake drum side.
9) I had to tap the hub side bearing out using a drift and hammer, you have to tap them out from the opposite side.
If you are replacing the bearing it's best to do the following, otherwise skip to 12.
11) You have to remove the locking ring holding the inner bearing in place. I found the best way to do this is to place a screwdriver in the notch of the retaining ring and tap it out. The ring is left hand threaded so you have to tap it sideways to loosen. There is a special vespa tool but who needs them! ;D
12) extract last bearing using a drift.
To re-assemble, you do it all in reverse.
1) Replace inner bearing and pack the bearing out with grease, replace locking ring.
2) It's best to freeze the axle or heat the bearing a bit to make inserting the axle easier. replace the axle so that the grooved end faces the drake drum and the threaded bit goes toward the rubber bung.
3) replace outer bearing with some more grease, followed by circlip and oil seal.
4) turn over and replace drive gears. I found it easier to temporarily fit the new hhub to tighten the speedo gear as you can grip it better.
5)Pop in the rubber bung.
6) Fit the brake pads and little circlips
7) slot on your 5 stud hub / drum, pop on the washer and slotted nut and split pin
8) pop on your rims and off you go. ;D ;D
5 stud brake drum hub and two part rim.
Hope it's of some use to someone.
J
