1971 T350 project

[AgentOrange]

Here they are, pretty much dent free and almost rust free. I'll have to cut the flange and get a T350 exhaust castle nut on there and reweld the flange back on. During the summer I can hopefully do a stock vs rz pipe dyno, thats if I even feel a big difference.

[Vintageman]

you don't have to cut flange off your T350 exhaust if nice. Look for a pair of gt380 exhaust pipe flanges. they screw off pipe and have same threads. Also they have mounting holes. If you put on backwards they provide a nice flat surface and place for exhaust gasket. You will have to grind down cooling fins so it screws on far enough.

http://www.ebay.com/itm/1975-suzuki-gt3 ... e3&vxp=mtr" onclick="window.open(this.href);return false;

[AgentOrange]

I'm not touching my T350 exhaust just the RZ exhaust. The yds3 I have has the same type of castle nut so I'll see if those fit first and I think they should have T350 castle nuts on ebay, I always thought the gt380's were bolt on flanges but now I have another option, thanks Vintage.

[Alan H]

The GT380 are bolt on flanges (to the exhaust port), but the flanges screw onto the exhaust pipes.

[AgentOrange]

Ah ok hopefully they have the same thread pitch as the castle nuts if the yds or gt250 ones don't work. Thats really an odd design.

[Alan H]

If you think about it, it's very clever as you can slacken the collars down the pipes a bit, then rebolt them to the barrels and nip up the gaskets a bit more when they start to leak a bit at the flange.
Dashed clever these orientals!!

[AgentOrange]

Should I plug up the pipes coming from the header? from what I read they are supposed to go to a reed valve. And would removing the catalytic converters do anything besides loosing some weight? (if its possible without butchering it)

[Alan H]

A reed valve would be on the intake - but the 350/315 doesn't have any. So unless you intend selling the spannies at some time, you might as well cut the pipes off and weld the hole up.
There aren't any catalytic converters on a two stroke. The oil in the exhaust would clog them up almost immediately. I think you mean baffles. These help keep the exhaust quieter, so by all means take them out and clean them, then put them back unless you have very understanding neighbours - and police.

[AgentOrange]

The RZ350 exhaust is the first ever motorcycle in the US to have catalytic converters equipped from reading around. From this link it appears that the RZ350's came with a few extra things compared to a normal 2 stroke. It looks like there is a small tab connecting the two halves, I believe I can separate the exhaust, remove the catalyst and then reweld the tabs back up.


http://www.rd350lc.net/pageCATA.htm" onclick="window.open(this.href);return false;

[tz375]

Those two tubes connect to an air valve IIRC. It's part of the clean exhaust system for the US market. It probably had reed valves in there. The PO of my RZ took that crap I mean stuff, off and fitted Spec 2 pipes for a much needed weight saving and performance improvement.

Catalytic converts are a great idea to burn off unburned hydrocarbons, but they clog up, and they hurt performance. It's OK to remove them from the pipes.

[Vintageman]

GT250 exhaust outlet is smaller diameter than T350

[AgentOrange]

Vintage, I don't know what I would do with out you, saved me about $50. I guess I should shoot for the gt380 flanges then if the Yds ones don't work. I hope the catalyst is the majority of the weight, these pipes are fairly heavy.

[Alan H]

Been 'looking up' and it appears that catalytic converters were used on 2 strokes in the US. Never heard of that to be honest. Best way ever to strangle performance. It's bad enough on a 4 stroke engine.

[diamondj]

A bit late to the party, but if you decide to go back to your designed chambers, cone engineering could probably roll them for you:

http://www.coneeng.com/

Jim

[Vintageman]

diamondj,

Welcome late anytime YBGI (You Bring Good Ideas).

I have read using a factory exhaust is a good starting point for custom chambers. First they fit. And, they always seam to have a good first cone and straight body to leverage. The end is always stuffed with baffled etc. though. But if you cut off end and add the final cone and stinger you will have decent set of pipes. Seen this idea somewhere not mine and can't claim it.

I have had bikes where no one made chambers and was always a thought for I could find OK stock pipes on eBay etc. good enough for cadavers, but a skill I did not have was making the cones or knew anyone who would for me even for $