Riff Ratt

[Wildcat]

I drilled some more holes and mocked it up. I was wanting to see how low it could go and still have pedal ground clearance. I think I'll be able to flatfoot it ok.
This is how my shop is supposed to look, "Ain't no flower show happenin' today!"

A few welds for the extensions and cantilevers and I'm almost there. How to attach the shocks to the cantilevers is a dilemma.

 

[Wildcat]

It wasn't too hot today, a tropical depression went over us last night and cleared the air.
I checked all the angles for the rear shocks and positioned the cantilevers to give the straightest action. Then I clamped the cantilevers in place and will wait for the welder to show up. Welders that make house calls! They actually did a lot of the railings, steps, and trim on my house recently and are always looking for work. The big sliding garage door works great. No car yet though. They also did my steel roof.
The rear extensions will also get welded in place. I've also come up with a plan for the rear shocks attachment.

 

[Wildcat]

I have some thin pieces of metal, maybe they were leafs on a set of springs. They are long enough to use as brackets for the rear suspension, as long as I use two of them for strength. That's the idea.
I measured them out for cutting and bending. I use a hammer and vise for the bending. I may need a new vise after this build.

the lower bracket will attach to the inside of the shocks, while the upper will attach to the outside of the shocks. I have 4 1/2" of clearance for the tire. The outer one goes on top of the cantilevers and the lower goes under them. If it turns out that the cantilevers can't withstand the load, I can easily run an extra brace straight from the seat collar.

The hole on the fender brace lines up perfectly with the brackets. I'm glad I didn't cut it off.

 

[Wildcat]

My new tube cutter showed up today. Off came the cantilever ends and I drilled some holes to mount the rear bracket.

My old drill doesn't hold a charge that well and a new drill is on order. But I was able to mock it up.

 

[MattiThundrrr]

This is turning out so cool, completely reshaping the frame! To me, it looks like it will need the brace to the collar. Those canti tubes are going to feel a lot of force! Also, the bb drop is concerning to me, how much clearance are you going to have?

 

[Wildcat]

This earlier mockup shows about 4 inches pedal height, which might be about 3 inches when I sit on the bike. The redo of the forks gave me an extra inch also.

I'll be able to adjust the pedal clearance by repositioning the dropout extensions or mounting the shock brackets both below the cantis for an extra 1/2".

I'm already working on a bracket that attached to both sides of the seat post bolt and slants down to the top of the bracket for more support.

 

[Wildcat]

I mocked it all up to get a better idea of how it's going to sit. I think it's good as it sits now.

 

[Wildcat]

More hardware today, so I bolted everything up so far. The swingarm took a half hour to bolt up. The rear feels nice and solid but the front was a little shaky, so I'm going to use some of the metal for 2 braces for the front and back of the front shocks. The one I had there was temporary.

I asked about the welders who never showed up. They weren't asked! So maybe tomorrow they'll show and weld up a few things for me. I've got it laid out and ready, just have to remove the wheels so the tires don't get damaged.

 

[OddJob]

I'm not sure where your seat stay brace is ( can't see it in this photo) located exactly, but maybe a mono-stay between seat tube and that would suffice for some more support? Continue along the same line as the top tube slope.

*Indicated by my ruff Riff Ratt rendering

 

[OddJob]

And btw, lots of cool stuff going on here , @Wildcat !

 

[MattiThundrrr]

Or a wishbone shaped thing made from a cut off fork crown or another stay. It would match the swingarm below

 

[Wildcat]

I think the support needs to be straight in line with the bracket to have the strongest effect. I think the two braces may bend at the corners as they take all the weight on the sides. If the bracing comes from the seat post collar it will be almost perfectly in line with the shocks. I'm going to try to make up a bracket that's wide enough to reinforce the top of the bracket and give vertical support at the same time, like a triangular brace that will attach to the bracket and use the seat post bolt as the way it tightens up along with the seat post. Here's my crude rendition of that idea:

 

[Wildcat]

I rethought it again, I think it needs to go straight, no slant to the bracket, then attach to an extra bar across the top of the bracket. That may be stronger, and only need one bar extending back from the seat collar. I'll lay it out tomorrow and see how it looks. The welders are coming tomorrow too.

I think the weight will be in excess of 55 lbs, so I ordered a center stand to hold that much weight. It's the same one as I used on my 42 Hawthorne, it doubled as a work stand with one wheel up in the air. It'll come in handy as I align everything.

 

[Wildcat]

A work crew showed up this morning to put in some flower beds for the wife and brought a welding machine. With just a pair of sunglasses the welder completed the welds on my frame. Many times there aren't any sunglassses so they try not to look as they weld with no protection. He welded right out in front of the house.

The welds look good, they even ground off some of the old brazing from the original cantilever points. All I have left to do is a brace and round off all the sharp edges of everything.

The dropouts also look good and solid. The frame is almost done.

 

[BartRidesEternal]

Looking good, I like your ideas!

I personally am a bit worried that the rear end will not have enough stiffness:
The hinge is quite narrow + the shocks are mounted on sheet metal which is not "boxed".
With boxed I mean completely closed on the top and bottom. This can be done with a welding session or mechanically.

I made that mistake with my "crossframe" bike, where I used a 5mm (S355) steel sheet on the chainstay where the fat tire and the crankarms meet. I stiffened this part afterwards.

But: I love your frame shapes so far!

 

[Wildcat]

I'll probably run into some problems as I test it out on the road. Having welders easy to afford is a big plus. I was going to box the fork tube for the hinge, but am using locknuts on either side and it seems very solid, but I'll see for sure in a week or so.

I still have a brace to go from the seat tube (where the collar bolt runs through) to the top of the rear bracket, along with an extra piece for more rigidity.

 

[Wildcat]

The layback post arrived. It was heavy and the right size. I thought I would have to shim it like the last one. It will only go down to where it is because of the welding on the seat tube. No problem, I'll just saw the end off, but I can flatfoot it like it sits now.
I threw the parts together to have a sit. The rear springs do flex a little with my weight, and the front knee action is nice and soft with a lot of travel. No movement from the front shocks as I thought. There was a wiggle in the rear, I realize now the rubber bushings are allowing some play. They will have to come out.

 

[Wildcat]

Things keep showing up! My wall mount bike work station came in and I'll be mounting it on the wall today. 20kg limit so Riff Ratt can't go on it. I removed 6 of the bushings and will make a few big square washers to make it work. I took 50mm off the new seat post so it goes all the way down. Then I measured and laid out the flat bar for cutting and drilling later, it's too hot already. They are for the reinforcement of the rear section.

 

[Wildcat]

I bolted the shocks and everything back together after removing the bushings and adding big homemade square washers. That seems to have made a big difference. I get good spring action front and rear when I sit on the bike and it all seems solid. There's no extra support from the seat post, I'm hoping it might not need it. I'll keep a close eye on the cantilevers to see if they have any bend.
The new handlebar stem showed but the half moon bars are still somewhere in China. The center stand didn't work out, too low to the ground. Maybe a rear stand like the old bikes had would work.
I bolted the tensioner on to the extra hole at the bottom of the dropout extension. From the axle wouldn't have been enough spacing for the chain. Then I stretched a long length of chain across to check the clearance and it looks good. Tomorrow I'll splice together some old chains that should be long enough, put on a set of pedals and it might be ready to test ride. Getting it out of the bunker might be a problem.

 

[Wildcat]

I've tried different struts on the front and it still doesn't work well enough. They don't flow with the extension angle at the bottom and seem too small for the shocks. It looks like a second set is needed to bolt up to the back side of the shocks.

I like the extension but it needs to be in line with the fork arms and struts. So I'm thinking of ditching the shocks and making up a pair of struts. They'll be curved to match up with the angle of the extension at the bottom and be about 25" long. The shocks aren't doing any real action anyway, the knee action spring is doing all the work.