trials modifications, my lucky tips
Posted: Sun Jan 20, 2019 7:21 am
I'm modifying an Ace frame for trials riding at the lower vintage class levels. I wanted to modify the rake mildly, taking 2 1/2 degrees out of the neck. The backbone and the under tube were cut with the two down tubes left intact, then the neck shoved forward to where it read 2 1/2d less on my degree wheel. The Hodaka's frame is made of thin walled tubing. 1 1/2 o.d. exhaust tubing fits exactly over the 1.37" backbone, making splicing easy. Splints can also be welded in to make the area stronger, though with the short distance spanned it shouldn't be the weak point in the back bone. I made some plate splints just in case.
Similarly, the tube under the backbone can be spliced using 1" o.d. thin wall tube. 11/16" o.d. tubing fits snugly inside, making a double thick joint of the under tube easy.
Serendipity. What I feared as a complicated job fell together with scrap I had laying around in my shop. The tubing was leftovers from Tractor Supply or Home Depot and the auto parts store.
Similarly, the tube under the backbone can be spliced using 1" o.d. thin wall tube. 11/16" o.d. tubing fits snugly inside, making a double thick joint of the under tube easy.
Serendipity. What I feared as a complicated job fell together with scrap I had laying around in my shop. The tubing was leftovers from Tractor Supply or Home Depot and the auto parts store.