Passing the tinkering torch

concours said:

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concours said:

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robs ss said:

If you are going to do that many photos maybe think about reducing the size to below 500K.
I'm leaving the thread after waiting too long for the pictures to load.
Only 5 words?

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robs ss said:

If you are going to do that many photos maybe think about reducing the size to below 500K.
I'm leaving the thread after waiting too long for the pictures to load.
Only 5 words?

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Elfix said:

I would add that this mod won’t get you any real performance improvement all by itself- the bike will just be able to remain sharp and peppy as it’s run. I’ve been very happy with the results on my RD and no longer get worried riding it for longer trips as it never seems to suffer like it once did.

Klemm also did the head of my 1972 RT2 and the average cylinder head temperature dropped 100F. It was a very well done mod with very positive measurable results.

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Elfix said:

I have a mostly stock 1973 RD350 and there are two mods I’ve done that have made it much easier to live with.

The first was a powerdynamo charging and ignition system, which replaced everything that spun or made sparks. This got rid of the points in favor of an electronic ignition, replaced the dodgy stock coils, and provided a more stable charging system. The work done by the Op covers much of this, and they will probably be just fine with their mods.

The second thing is a bit more wonky. My RD and all of the others I had ridden suffered from heat soaking on long rides- once run for more than 30 miles or so it would “go soft” and lose power. It could no longer pull to redline in the top gears and had to be run in 5th to maintain a nice highway cruise.

The cause is too much heat migrating into the cases and overheating and reducing the density of the incoming charge as it passes through the cases. The engine is still getting enough lubrication and no damage is occurring, but you’ve lost a good 30% of your power, and if you continue to run it hard you will eventually overheat the engine.

The best solution I’ve found is to send the heads and barrels off to Klemm Vintage and let him reshape the combustion chamber shape and squish. His mod allows the engine to run more happily on 90 octane unleaded and decreases the squish band clearance enough to allow the pistons to better liberate their heat into the head where it can be shed- instead of baking the cases.

Simply reducing them squish clearance to .8 mm will help tremendously, and this can be done by changing head and base gasket thicknesses. Cometic has lots of options.

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concours said:

Nephew's 1975 F11
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Yorkie said:

My youngest asked if we could build a bike together so we picked up a ‘71 Yamaha AT1 to work on. We went completely through the bike together. Lots of trips around California hunting down parts and meeting grumpy hoarders. He got it running and road it around local parking lots until he decided to sell it fund a dirt bike. In August he heads off to Texas Tech to study Mechanical Engineerung. Couldn’t be more proud.

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acotrel said:

My project bike is an H1 Kawasaki bottom end with RD350 reed valve cylinders in an Egli copy frame. The motor has TZ750 port timing, and a Krober ignition. It's capacity is 600cc. I need to make chambers for it. I think I must have been insane when I started building it. The running gear is

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acotrel said:

My project bike is an H1 Kawasaki bottom end with RD350 reed valve cylinders in an Egli copy frame. The motor has TZ750 port timing, and a Krober ignition. It's capacity is 600cc. I need to make chambers for it. I think I must have been insane when I started building it. The running gear is RG250Suzuki.

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