Project X

[teazer]

You are correct that a GS or GSX has oil fed directly from the oil pump through both gear shafts, so it is important t get enough oil in there.

Thinking out loud for a moment, early TZ's and RDs relied on splash lubrication but later V twin racers had a transmission oil pump.

[madforitkev]

Fun with clutches........

So I looked at just buying a TR dry clutch from BDK. Nice kit but heart failure territory!!!

dry clutch bdk.jpg (9.45 KiB) Viewed 1170 times

So being a bit tight and needing a challenge (I have issues), I decided to make this kit based around a Honda RS250 dry clutch. The fun begins.......

Ok so I bought a BDK casing, I just couldn't be bothered with that hassle as well.

Next was disassembling the GT clutch to make .....

Now I need to graft the RS inner gear to the GT out on the primary....

After lots of pain and line up issues I have a GT/RS primary!!

I've already got the close ratio GS gears to fit but I have to do some mode to the clutch shaft to;

Fit the needle roller with a retaining circlip machined into the shaft to stop it moving too much (a little play is needed as on the GT)....

This meant modify the bearing side thrust washer to make it thinner in the middle so all the tolerances stacked and the gear didn't foul the casing but also to allow oil to the needle bearing. I also had to cut a new hole in the shaft under the bearing to let oil flow (and block the old GT one on the shaft).

Next came the clutch basket. I didn't like the steel RS one and Talon make a cool ali one. Only problem is when assembled it wont all fit in as it all screws together from the back. So I had to change the design and make a new back plate so I can assemble it all from the front..

Now the cush drive plate can go on (no more rattily springs)!

And the basket (screwed from the front)...

Then the hub...

Notice I have adapted the clutch to be a push rod (hydraulic) drive. Slave cylinder to be grafted somewhere on the final drive side. Just had to open up the GS shaft end and fit a seal.

[madforitkev]

So after a few months of pain, I finally have......

Tada!!




There is a minor detail I left out of the early post in that I needed to make a bronze bush to back upto the needle bearing circlip and via an internal O ring seal the shaft. It then had a radial seal around the basket inner gear (bit with the cusht drives in), that basically keep all the oil the right side of the casing.

The other end of the bush fits against the hub back and transmits the force onto the lock nut on the shaft end.

Anyway it seems to spin OK and doesn't grind too much so hopefully that is that.

Next the reed valve conversion and the squish head skull caps for the cylinder head. Both are basically done bar fettling so I should be able to post soon...

Remind me again why I started this? Oh yea the 'issues'...

[madforitkev]

I am still a bit worried about oil feeds to the clutch shaft.

I haven't changed the output shaft feed system so I'm not bothered about that.

I have added an oil way in the clutch shaft for the needle bearing and am hoping the splash from the primary will be enough.

The oil for the clutch shaft/gears in the gearbox is now only splash fed (the GT had a feed from the clutch end). I might try to add a splash route to the opposite end bearing (to the basket) to at least get oil at that end of the shaft. Now I have a central push rod I will need more lube in there anyway. The GS has larger shaft oil holes that the GT so I am hoping that is enough.

Any thoughts anyone?

[madforitkev]

Just got the squish head bits back....

So the problem is when you bore out the head to insert the domes it is very height restricted and the casting heights for each head are different so there is a different depth for each head to sit into!!

Obviously not easy to see that until you start hacking!

The end goal is to have 3 replaceable skull caps all the same so I can easily retune and make a new set so in order to achieve that (and be able to make all the O ring seals work), I needed to make an interim spacer for each head that is a different size.

That means the skull caps are now all the same

And when the O rings are installed in the grooves they fit lovely....

All held in place by the cylinder head bolts when they are tightened up. The head to barrel seal is an O ring system now so no room for movement of the caps.

[Kettletimes3]

That's interesting i've not seen it done like that.
Nice by the way.

[madforitkev]

So to the starting system.

I wanted to save weight and also to remove the large alternator.

Then I remembered the good old GT185 with its Dynastarter, basically a DC generator and a starter motor that uses two coils, one for each.

If it is usable I save......starter motor, alternator, starter clutch and a few bits and bobs.

Doing a rough look at the starter watts it seems to be around the 750 starter power.

Tricky bit is it fits on the LHS where the timing goes. First step find a self generating race ignition that fits on the RHS. Quick internet search and they are available (more later).

So how to graft the rotor onto the crank as they have different tapers?

I made a 'taper adapter'.

Basically a different inner and outer taper with an internal and an external woodruff key.

Tada the rotor fits.....

and the stator kinda drops on but casings and mounting are the issues.

So I made a spacer plate to bolt to the crank cases and sandwich between them and the engine casing. This provides the stator mount.

Obviously I have to shape the outside of the plate to match the casing......later


Next make the casing fit the assembly. Luckily the standard kettle casing is way large, so I sliced a section out and bored out the central ignition mount area.

I then had to make up a spacer guide to fit round the rotor brush area to make sure the stator when located on the backing plate stays central. With that in place I can drill and line up all the casing and stator mounting holes.

With that done and the old front section of the casing weld metalled on again, I have a new shorter GT casing that tales the old chrome cover......Nice!

Minor fettling left then ready for a test fire!! Fingers very crossed.

[swarrans]

Fabulous work!

Simon

[madforitkev]

Fired up the old GT185/750 starter generator tonight.......

It only works!!

Spins at nearly 5 ft-lbs torque like a mad thing AND produces 12v DC!

Obviously this is a test without the full engine assembly but I'm not raising the compression ratio much, so we should be good to go.....

Happy days.

Back to the frame mounts now...

[Kettletimes3]

A lot of interesting work going on there.