Paul's TZ

[mellorp]

Hi Phil,

Might be a random question, but are you throwing the old pistons away? If so, if i pay postage can you send me them please? I'm interested in finding out where the cracks started.

Thanks

Dan

Sent you a message

[mellorp]

With the road tyres fitted we are off to 3 Sister on Tuesday for some 10 min dash sessions
https://threesisterscircuit.co.uk/bikes/bike-attack

[mellorp]

The TZ needed a little TLC. After it fell over and fell on my RC8, knocking it over than landing on top of it I was less than happy. Smashed fairing on the TZ and broken bits and scratches on the KTM as it fell on top of the stand that was about to be used for the TZ. FFS. Fortunately  I had a spare fairing for the TZ, painted at the same time as the original. Fitting it was a bit of a fiddle as it's a 4DP faring on a 4TW. The mounting points are slightly different. With a bit of re drilling the new fairing is on.
A re routing of the PV cables was needed, along with the on/off switch, then the brake lines, then the throttle cables. Everything I touched needed something else to be moved. It's all a tight fit in the nose cone with the dash, Zeeltronic, PV motor even though everything is neatly packed together. There are 6 cables in there, 4 for the PV and 2 throttle cables, and they run close to the brake lines. Move 1 and they all need to move. Anyway it's all OK now
A check of the plugs and it's running rich. Which is OK as it's quick and less likely to seize. If it were being raced I'd be looking at jetting it down. It's quick and so far reliable. But as it has TZ pistons they do need checking quite frequently. Being a TZ this is an easy job. Just a pint to take the barrels off just to look at pistons. You can't have it every way with a tuned 2 Stroke. I might raise the rev limiter as it's set at 12k which is stifling the TZ and those massive carbs just a bit
When riding it at Anglesey, there was a quick rider on an Aprilia. A video of that bike was showing just short of 120 on the main straight and my TZ was pulling away from it. The guy was a demon on the brakes and I didn't feel like pushing harder to chase him. Given a bit more road I get the feeling the TZ will top out at about 140mph. No chance of me trying that on the road. I hear prison food isn't that great
I've also gone from 50:50 avgas to just super unleaded so 12,500 should still be safe. I've also moved away from Castrol 747R as stock seems to be very low. I now use the alternative Castrol XR77 but still at 40:1
Maybe a few more road outings are in order, just not 140mph road outings :-)

[yanw]

Maybe a few more road outings are in order, just not 140mph road outings :-)

Don't take the GoPro on the road. Fozzy once told me about a guy in South Wales who got nicked, the police reviewed his camera that had the incident and also many others from the previous three weeks and he got six months...

[rz500guy]

Just saw this post and nice to see it on the track. I did not read the entire post. Is this a real TZ engine. What year is the engine? And do you think 40-1 is enough oil and the use of super is enough octane? I am at 28-1. It seem to get along well. 140 is tough on a TZ. You need  a long enough straight, proper gearing, and jetting should be as close to optimum. I have seen 141 at COTA and that straight is almost a mile long. Keep us posted and videos please

[mellorp]

John McGuiness averaged 118mph in the 1999 IMO TT. Anstey topped that with 120mph average in 2017. Top speed on Sulby was about 160mph. I doubt my TZ is that fast but back in 1981 TZ250E hit about 130mph on Sulby Straight

[mellorp]

I took the TZ to the Donington Park CBT day. It sort of went well for an old thing with an old bloke on board. It started to make gurgling noises so I backed off quite a lot. It was still going well so I got going again, just treated the old thing very gently

https://youtu.be/UQYXlhuyxSI