cradle modifications for race

Hello,
With my little technical english i don't arrvide to find photos or indications about this modification to reduce the side movements :



I know there is diffrents variants without modications welded, can you help me !

Do you want more information about this modification??? Not much more than your photo... Build it and fit it in to hold rear of cradle very steady and in alignment with chassis... There are more photo's here of this modification.. Other people will have more information and will come in...

And or are you asking about the swingarm /pin modification...

not-another-spindle-thread-t5978.html?hilit=keglar#p58638

heinz-kegler-clamps-t18463.html?hilit=cradle%20mod

That looks nice - the rose/heim joint link modification to limit lateral movement. Is that a kit or home made?

I think the OP is asking if a similar link can be fitted WITHOUT welding, making it an easily reversible modification.

concours said:

I think the OP is asking if a similar link can be fitted WITHOUT welding, making it an easily reversible modification.

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Yes, exactely. I see other photos wiith other fit but i don't know how to find them.

gillou said:

concours said:

I think the OP is asking if a similar link can be fitted WITHOUT welding, making it an easily reversible modification.

Click to expand...

Yes, exactely. I see other photos wiith other fit but i don't know how to find them.

Click to expand...

I've seen many head steady clamp ons, but never any lower/rear mounts clamped on. If it exists, then soon the images will appear here. That one in the image you posted, looks like a great job. If I was going to do it, I'd copy that one. Elegantly simple, not oversized brackets.

Have you improved your swing arm spindle mounting? The Image also shows a good job there too. Here is the simpler, bolt on method:

Isn't that doing what the adjustment at the end of the pivot is supposed to do ? The link with the rose joints seems more sensible. The end at the frame cold be bolted to a clamp ? One each side would force the motor gearbox assembly to rotate in only one plane, however I hate to think what the effect of vibration would be on the metallurgy. I think it might be easy to underestimate the forces involved.

If you run your ISOs tight-ish, and have a linked head steady (like the Dave Taylor or Jim Comstock versions), then the engine will be mounted in 3 good points, by 'mounted' in this context, i mean mounted in a way that controls lateral movement. with these 3 mounts, the only lateral movement is that allowed by the ISO settings, which having set them tight, is not a lot.

What I mean by all this is; I fail to see the advantage in the bottom link, and or pad, set up...

Why is it any better than simply running with a tight ISO set up?

ludwig said:

Fast Eddie said:

If you run your ISOs tight-ish, and have a linked head steady (like the Dave Taylor or Jim Comstock versions), then the engine will be mounted in 3 good points, by 'mounted' in this context, i mean mounted in a way that controls lateral movement. with these 3 mounts, the only lateral movement is that allowed by the ISO settings, which having set them tight, is not a lot.

What I mean by all this is; I fail to see the advantage in the bottom link, and or pad, set up...

Why is it any better than simply running with a tight ISO set up?

Click to expand...

You are absolutely right that a good headsteady and tight isos are the most important .
I set my front iso at 0.10 mm and the rear at 0.05 mm .
Still there is plenty of flex in the frame and the wear marks on the engine plates are an indication that the pucks do provide some extra support .
I see it more like an experiment than a real improvement ( bike handles exellent without it ) and it only added some 150 grams of weight , so..

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Well, I knew it wouldn't be heavy Ludwig, not on your bike!

Interestingly, I've got my ISOs set at kinda in between your front and rear settings at approx 0.0033" (an estimation based on how far I backed them off from snug compared to standard) and it feels very good to me.

When putting 'race to win' loads on isolastics and using radius rod or rub plates on cradle rear its not a bad idea to tie the back side of cradle togehter along with cross bracing the rear frame too. Two schools of thought on where to put various taming devices, close to the iso mounts to mimic rigid frame or far awayto retain magical light frame isolastics flexy compliance *w/o rebound*. The fork twist- rebound rate comes into play at some level too slapping back against the frame+links as highest turning loads hit & and release so consider [difficult] bracing fork to get more safety-comfort factor advantage. The Cdo power unit and frame over lap each other to help resist opposite end tire loads so my camp says link em together at far ends not near the middle. I found that tire pressure had significant influence on how tight or loose I set gaps to compromise between smoothness vs stabliity - harder tires allowed closer gaps w/o buzz. Too open gaps and sloppyness sense showed up again so I ended up with a bit over .01" at front and back. A race power Commando should be able to lift front out of traction topping out power band in lower gears while leaned - so better not be depending on front traction to steer just then... Untill ya know what how to handle that better not go around that harsh on anything.