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when you get it its obvious what you need to do. looking at the rod from the top, the roll pin is pressed all the way across the opening. take the middle section out, to clear the bottom of the bolt/nut that protrudes into the rod. a dremel with a carbide bit to cut it i think is what i used.

as a side note, i did add preload adjusters from economy on my bikes since the original post. mine is on the lightweight rd, its about 115? lbs lighter than a stock bike, so i had to tune mine lighter, i used 5wt fork oil and actually reduced the preload a hair.  however, i've done this the other way as well. I know, for a fact, these make a huge difference (the emulators) when set up right.  heres the instructions for the XS forks, which the top is different than the earlier 34mm forks.

https://www.2strokeworld.net/wp-content/uploads/lightweight-rd/forks/fork-valve-emulators-1.pdf

That damper rod in the instructions is the same as late model RD250 or 400.  but on a 350 they really need a racetech adapter with piston ring IMHO.

Most likely an F or G model ie Daytona. I'm not familiar enough with what was supplied to your market but I think they were the same as we got in Australia. The US always had a cost reduced model to suit the market dynamics.

I had a later one on a GT750 and it worked just fine.  My go-to place used to be Electrosport bu I just had one DOA new out of the box so I am now fitting http://sparckmoto.com/Products/Charging-and-Regulators on all my bikes.

With an electromagnet I use their 12v 3 phase unit.  Ask Matthew at SparkMoto to fit the right plugs and you will get the right unit at a great price. At least that has been my experience.

Last models of RD350/400 had different forks with different damper rods.  They changed to steel 17mm damper rods at least for Australian market.  Early models are similar to RD350 with smaller diameter aluminum damper rods.

The improvement from my perspective was the change to using a piston ring at the top which according to my very incomplete notes changed from 24mm to 27mm.  The top of later damper rods were also open with a bi-hex arrangement which is easier to hold in place than earlier rod which had two flats to try to lock on to.

On a closed circuit obviously   

No riding up here with 6" of fresh powder making everything pretty but no use for most of us with road bikes.

Timing sounds similar to where I am starting with an Ignitech, but on that, the base timing comes from the rear end of the trigger and like the Zeel, it is normally triggered by the front face and the ignition just retards from where it sees the front edge.

I am starting with base timing of 14 degrees, going to 28  at 1200 then dropping to 22 at 6500 and a8 at 8500 dropping off before the rev limiter kicks in. I have a 65mm stroke and long rods, but timing BTDC should be similar.  It's really a function of how fast the mix burns to get peak pressure around 15 degrees ATDC.  At lower revs, off the pipe it burns slower and with decent squish and higher than stock compression and JL pipes I am expecting it to need a lot of timing at low revs and about 20 degrees at peak torque and less after peak to heat the pipe and stretch the powerband.

When I drag it to the dyno I'll start with less advance than that - probably a flat 20 degrees and then add thee degrees everywhere and see what happens.  Where that increase in timing adds power, I'll repeat the process until we get to what the motor needs.

I like a lot of compression and this motor has a Chris Livengood welded and machined squish head, so that should make a difference to timing needs.

But back to the TZR, what is causing it go lean or just the cold, dense air?

I like to use RaceTech adapters with seals to provide a better fit and to allow for oil flow around the adjuster lock nut.

That's good to know that for an RD they are a well priced alternative to Racetech or YSS.

That's a lot of initial timing.  Do you think that's because at lower revs the exhaust and ports are way off optimal timing so it needs a lot more advance to get the party started? 

Makes me wonder what the timing curve looks like.

GT750 had timing at 22 degrees +/- 2 degrees and it doesn't make a lot of difference which end of that range it's set at for a stock motor. But that's the opposite end of the spectrum in terms of specific output and makes about the same power (stock) as an RZ350 or a good late model 250cc twin.   

So it's really a Chevy 350 is what you are saying... 

I have had no issues with CI parts.  I suspect that some of the cranks may have had rust pits where the seals run and that can ruin seals.  It's not unusual to have to ship two cranks to Anoka to get one good set of parts out of it.  Usually, minor pits and scratches can be polished out but if they are too deep, parts need to be replaced and use a bearing sleeve.

Bill Bune's team are familiar with our cranks and know what to do to ship back a good crank that should last for years.

Some people just don't like CI parts I guess.

With any non standard ignition system, the hardest part is accurately setting the base timing.

To find TDC I use a positive stop and degree wheel and make sure that it's zeroed half way between the stop BTDC and the stop rotating backwards towards the same angle ATDC. Inevitably what I though was TDC is actually 5- 10 degrees out. 

Using a DTI to set timing Xmm before, I don't need to do that but when the programmable system is set in degrees, I have to get the base timing absolutely correct because if not, the whole curve will be out by the error in base timing.

With limited access to fit a degree wheel, it all gets to be more complicated as you show in that video but where you can use a degree wheel and positive piston stop, and then confirm base timing with a timing light works for me.

41mm conventional Katana forks are suitable if a bit heavy and look right.  I have a pile of forks and weighed a bunch of them a while ago which is why I became a big fan of the FZR400 forks. They are very thin wall and much lighter than any other conventional sets I could find including RD and TZ forks.

With RD/TZ forks, there's not a lot of difference.  Damper rod designs are better on a TZ but I have seen sets modified to work more like an RD and with modified foot valves and so on.  The set of TZ forks I have was revalved by 4&6 racing years ago and what they did was to braze fill the damper rod holes and re-drill them.  Rinse and repeat until felt right.

Later RD forks are 35mm and are a slightly better design than earlier designs but a set of Mike's XS cartridge emulators is all you need to make them work. 

For that bike, I'd keep it period as far as looks and use conventional forks. preferably not to chunky though. XS650 or TX750 forks will also work.

This might not be the shape you are looking for, but...


https://www.ebay.com/itm/265909587325?var=0&mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=5338590836&toolid=10044&customid=786cd9c5eb0c15e5c2fbba0d2db3723e

I used a Busa shift arm on a GT750 IIRC to create a set of rearsets, so I would guess that any model Suzuki with the sort of lever you are looking for would work.

A GSXR or GS lever might work or look at an RM off road model.

That's basically what I did on a TZ350E IIRC.  I had a late model A/C 250 or 400 back in Australia that i grabbed the parts from.

I also had a set of TZ forks re-valved years ago and it took the suspension guys for ever to get them within the ballpark of what might be considered OK by modern standards. 

That set will go on the Spencer replica with Champion frame, but if I were to build a street RD again, I think I'd fit a set of FZR400 forks.  They are so light compared to almost anything else out there.

Interesting point about costs. 

I have a set of badly dented Jemco pipes here that were mauled by a minivan driver not paying attention. So I need to replace probably 6 cones and the belly part of all 3 and if I buy those at say 80 bucks for a rolled and welded cone, that' adds up to 720 bucks plus there's some assembly required.

So I shall buy a sheet of 20 gauge mild steel, create templates, cut the sheet into parts, roll them and weld them and I am guessing that at a moderate hourly rate that would still cost the owner almost as much as a new set of pipes.  At least we can still use the stubs and headers and probably the rear cones and mufflers.

There's a lot of work in making pipes and it isn't cost effective unless you make them buy the truckload. No wonder JEmco and DG and Gary S want a lot more for pipes than they used to.