SP370 swing arm

[James Lee]

Looking for a stock SP370 swing arm to extend mine or an alloy DR unit or profab or similar.Cheers,James.

[Krikey]

Looking for a stock SP370 swing arm to extend mine or an alloy DR unit or profab or similar.Cheers,James.

I've got a couple of alloy PE twin shock ones?

[LWC82PE]

if you are not fussed with going slightly newer then i think one of these would be better than modding the stock round tube one

This did not sell

http://www.ebay.com.au/itm/Suzuki-DR500-Swingarm-/231950428715?hash=item360152aa2b%3Ag%3AQn4AAOSwY3RXJsJ0&nma=true&si=CVVBuUkKb3vONKv5b89yU9D5FxU%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

If i had more time  i would make a pattern/drawings of my alloy ones for you.

[Oldfart]

Be wary of pivot pin differences ......Dr 500 arm into a Sp 370 will fit, but will need a different size bearings of which are NLA to make it happen
.....make them out of bronze.   
 C2   arms drop straight in.
Pe  175  T/X work well also with a bit of fine tuning at pivot spacing.



 

[LWC82PE]

I know you can make DR500 to suit 14mm pin ok just by swapping the 16x20mm spacers to 14x20 as i have done it. No need to change bearings (common IKO needle). From memory 78 SP has 14mm and 79 has 16mm? (PE250  T/X/Z has 15mm) I know my aftermarket ones were for 14mm so must of been for 78 models. PE175 use 12mm pivot pin.

[James Lee]

Thanks for the great info,I really would like to mod the original as I have plans of making it look quite trick and it retains the vintage look of the bike,if I was going to go with DR I would prefer alloy so there would be a trade off between looks and weight saving.
My SP is a 79.
I trial fitted my RM125N swinger but when I saw the difference in pins sizes I just slotted the stock unit back in for now.

[LWC82PE]

The Protec and WB arms are 495-499mm long from pivot to  center of axle slot and the shock mounts are 431-433mm from the pivot. I cant give anymore finer accurate specs than that until i measure them up accurately in a jig again rather than just eye balling with a ruler. But that gives you something to go by anyway. This enabled a decent length long travel shock (WB gave you option of Curnutts, Works perf or S&W in 1980) with a long stroke to get the travel close to 9" with swingarm at maximum acceptable angle. If shock mounts are closer to the the pivot it means a shorter shock with less stroke and you gain nothing (if keeping swingarm at max angle) because you loose out on shaft travel. Its all tied up with the distance between the top shock mount and the pivot location. With a large distance here it works out you get the most travel with long shocks with the bottom mount nearer the axle. If you had a banana swingarm that certainly would change things though.