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Rattyoz
24-05-2017, 12:21 PM
Howdy, Im off to Phillip island for the Hartwell round at the start of June and I would like some advice on gearing for PI. Would it be fair to assume the gearing would be similar to what used at SMSP? Mainly after advice for main straight to ensure in not overreving the piss out of the bikes, as I will be running in a motor in the first few laps. My Yamaha TZ250 is currently set up with 14/38 ratio which is slightly overgeared for SMSP turn 1 by about 500 revs, so maybe one tooth less on the back to a 37?
Cheers for any advice

Marshy
24-05-2017, 09:41 PM
Hey mate, yep, one down on the rear is pretty much spot on for most bikes. If you're not quite maxed out at the Creek, you can often get away with the same gearing... even if it just sits on the limiter for a hundred metres or so ;)

Rattyoz
24-05-2017, 10:14 PM
Cheers for that. Ya I've been given advice before to gear the bike to be sitting on the rev limiter well before the 300m board at turn one so the bias is for max acceleration around the circuit verses max speed potential but its a twenty plus year old bike and I would rather lean towards trying to keep the bits inside the engine for longer.

Nelso
26-05-2017, 08:22 PM
I reckon if you are 500RPM down at EC, you will be just about spot on at PI, unless you have a tail wind down the straight. The wind direction at PI has a significant effect on top end speed for smaller bikes. I'd take a 37, 36 and a 39 just in case.;)

Rattyoz
08-06-2017, 10:09 AM
Thxs for the advice fellas, ended up running with the 39 rear most of the weekend, just had a small headwind which held the bike to 12.5 k revs under the bridge and into turn one. Was real lucky to get three days in a row of good weather with only about one small rain shower late on the second day. Hartwell club who ran the meeting was great to deal with and the club members I meet were very welcoming. The club had a race class for just about anything and I was able to cross enter into two classes on both bikes. I ended up only running the TZ due to a seizure on the aprilia.

It felt like a cross between the PCRA and St George race meet with a mix of the latest modern 600's and 1000's and a healthy mix pre modern bikes and a few P5 bikes and sidecars. Most races were 5 laps with the buckets and juniors given 4 laps races. They had a few longer races for the modern and big bikes with a 20 min plus one lap feature race.

I intend to head back there next year if I can, but as I was warned several times by the locals, don't expect to get three days of good weather at the island in June next time.

Highly recommend doing the Friday practice if you can, allowed me to start getting my head around the speed of the track plus it meant I could leave my bikes and kit in the garage overnight. Was able to get my bikes, gear and entry paperwork scrutinering finished on the Friday afternoon which made for a more relaxed Saturday morning

zedsled
08-06-2017, 04:12 PM
Sounds like a blast.
I know my P5 Z750 works well with a 39 at PI.
Will be great to get back there again soon (After Winter)
You are flaming lucky to get 3 good days in a row...Hell, I went there in late December once and was lucky to get 22 degrees with intermittent showers!