pre oif a65 swingarm options, swaps, extending etc info..

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covered front end options for this model/frame in another thread so...

tons of info out there for back end options for other makes/models, just gonna ad pertinent info here as i run across it,

turns out, goes back ..some time in this info from ~ 66 (click on pix to enlarge),
http://showandgo.blogspot.ca/2009/12/extended-swing-arms.html

http://victorylibrary.com/brit/chassis-2a.htm

from an ebay ad google - BSA C15 B40 B44 Victor trials vmx vintage motocross mx AHRMA swingarm extenders
For sale a pair of machined pieces of steel to extend the swingarm length of your BSA B44 Victor or smiliar framed C15 and B40. With these installed you will have the swingarm lengthened 1 1/2". Our vintage mx team built and raced several BSAs with AHRMA back in the 1990s using these which improved handling. We had several sets manufactured and this listing is for a set which was never installed. You will need an expert welder to install these properly on your swingarm. Once installed the swingarm will need to be reinforced/braced as shown in the pictures. Keep in mind with an 1 1/2" longer swingarm this will also require a longer chain, brake rod, and the rear shocks may need to be set up differently (not the shock mounts but the shocks themselves). The bike pictured is the last BSA from our race team which I still own and ride. This BSA is not for sale and is pictured only as an illustration as motorcycle which has the modification using the items listed for sale.

https://www.a7a10.net/forum/index.php?topic=10028.0

https://www.a7a10.net/forum/index.php?topic=10028.msg73591#msg73591
yes you can fit a A65 swing arm in an A10 frame
 
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If you have a cut-off wheel, torch, welder, grinder, lathe, mill, and stock materials, you can make ANYTHING fit ANYTHING.

There is a nice, simple swingarm bracing scheme for classic Britbikes also.

These welds were NOT mine, I inherited it; I beefed up the birdpoop stuff to where it actually adds strength...

pre oif a65 swingarm options, swaps, extending etc info..
 
I cut 2 C15 swing arms so the 4 cuts when the halves were swapped gave 1" longer arms on one swingarm plus some bits which could be used to make a short one, but are in the scrap bin. Into the longer arm joints I inserted some short sections of tube with OD matching ID or the swingarm tubes and left 1/4" gaps for a welder to fill and joint the halves up. Dressed the weld and ended up with an extended C15 swingarm.
 
looks like there were 3 diff swingarms for pre oif a65, for years 62-4, 65-8, 69-70, no details yet other than mounting part(s) diffs for 65-8 vs 69-70
https://www.draganfly.co.uk/index.php/bsa/bsa/a50-a-a65/1967/category/271-swinging-arm

https://www.draganfly.co.uk/index.php/bsa/bsa/a50-a-a65/1970/category/347-swinging-arm

i'm gonna focus on 67 cos thats what i have

If you have a cut-off wheel, torch, welder, grinder, lathe, mill, and stock materials, you can make ANYTHING fit ANYTHING.

i don't have many of those skills, or experience, in making a change, first thing most folks look for/at is what options & info is out there, having access to info allows easier decision making to then move forward with,

if you google xs650 swingarm swap, there is tons of available info, along with other makes & models vs practically diddly for a65,

ran across some stuff tho, an oif a65 deal
http://www.bikebound.com/2015/08/11/1972-bsa-thunderbolt-custom-hill-climber/

high end
http://www.malarkeyengineering.co.uk/bsa-a65

vs home brew
https://www.ebay.co.uk/itm/1969-BSA...576678?hash=item43c3e818e6:g:hWYAAOxydlFSr111

_______
i'm looking for all dimensions like these
http://www.xs650.com/threads/swingarm-pivot.35933/#post-363215
xs650 - Pivot Tube:
ID - 16.02 mm - (0.631")
OD - 21.95 mm - (0.864")

norton mk3 spindle OD
https://www.oldbritts.com/13_100005.html
Swingarm Pivot Spindle, MK3, .8745" O.D.

a65 pre 69 "Spindle Diameter: 5/8" (16mm)"
https://www.feked.com/bsa-swinging-arm-spindle-solid-type.html
5/8" = 0.625
_______

some of the options for xs650
http://www.motolanna.com/ourshop/prod_2637748-Swingarm-Aluminum-Alloy-SuperLite.html
key point, the SR500 and XS650 swingarms have the same pivot dimensions
http://www.motolanna.com/ourshop/prod_448876-Swingarm-Aluminum-Alloy-SuperTuff.html

other stuff
https://www.ebay.com/itm/XS650-xs-6...brace-weld-on-kit-1-joe-wiseguy-/263209242491

https://www.ebay.com/itm/XS650-xs-6...wder-coated-braced-new-bushings-/263121267436

https://www.ebay.com/itm/XS650-xs-6...-weld-service-xs400-rd350-sr500-/391850435325

https://cognitomoto.com/products/xs650-weld-on-swing-arm-extenders

http://www.xs650.com/threads/b-1982-3-25-extended-swingarm-125-b.42154/

diy jig
http://xs650temp.proboards.com/post/29281/thread

it would be sweet, if a xs650 swingarm swap was doable via some cheap easy mod,

pretty sure the yam tx750 swingarm, bit bigger, beefier & longer is a direct bolt in for the 650 frame

some mods with a kz1100 conversion,
https://www.kzrider.com/forum/11-projects/599144-another-kz1100-cafe-streetfighter-build#684560
luv this guy, sez in the thread "This is the first engine I've ever worked on, so any tips would be very appreciated" lol
 
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