So I suppose all this is why a GP125 is approaching Manx Norton prices on Trademe?
Well done TZ, probably why the 'powers that be' wil never allow air cooled 125's here.
Hardcore Biker
So I suppose all this is why a GP125 is approaching Manx Norton prices on Trademe?
Well done TZ, probably why the 'powers that be' wil never allow air cooled 125's here.
Forum whore
http://www.trademe.co.nz/Browse/List...x?id=452663122Originally Posted by 2T Institute
So I suppose all this is why a GP125 is approaching Manx Norton prices on Trademe?
Well done TZ, probably why the 'powers that be' wil never allow air cooled 125's here.
didnt even get a $20 bid, now where are those nortons.
My neighbours diary says I have boundary issues
Forum whore
the truth is the fuel cap is damaged and i cant get fuel into it easily i dont know if the oil pump is working and i dont want to risk damaging the bearings or piston. its 6v im sure and i dont have a 6v charger to peak it up im kind of selling it as is cause i havnt had it running. tomorow ill wip out the plug and read it to see how its been running im good at reading 2stroke plugs i can tell its state of tuneby the plug. ive kickedit overslowly tosee comp and its good and its dry too. 10:37 pm, Sun 4 Mar Seller Comment: i pulled out the plug its been running fine by the looks of thr plug little bit rich maybe
thats maby why it didn't get a $20 bid
it's been sitting for how long and he can read the state of tune by doing a plug chop
"Instructions are just the manufacturers opinion on how to install it" Tim Taylor of "Tool Time"
“Saying what we think gives us a wider conversational range than saying what we know.” - Cullen Hightower
Forum whore
the truth is the fuel cap is damaged and i cant get fuel into it easily i dont know if the oil pump is working and i dont want to risk damaging the bearings or piston. its 6v im sure and i dont have a 6v charger to peak it up im kind of selling it as is cause i havnt had it running. tomorow ill wip out the plug and read it to see how its been running im good at reading 2stroke plugs i can tell its state of tuneby the plug. ive kickedit overslowly tosee comp and its good and its dry too. 10:37 pm, Sun 4 Mar Seller Comment: i pulled out the plug its been running fine by the looks of thr plug little bit rich maybe
and the auction was for a $20 key
how much do you pay for a manx norton key ?
"Instructions are just the manufacturers opinion on how to install it" Tim Taylor of "Tool Time"
“Saying what we think gives us a wider conversational range than saying what we know.” - Cullen Hightower
Forum whore
Neels sent me a drawing of a TZ350F pipe he measured, but I also got a drawing from Bod Haldane ( Yamaha Factory ) and there are several quite big differences.
I will just have to measure a set for myself.
Bugger.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
No8 Wire Extraordinaire
Well my last GP I bought in large parts for $50. Just assembled it & ran great. Sold it for $150 which recovered the two $40 knobbies I'd put on it.
What?!?
Anyway it lives on & is back to road tyres & a riding school hack. Best one he's had, & he's had it like 10 years.
Don't you look at my accountant.
He's the only one I've got.
Hardcore Biker
From a quick google images search under "TZ350 pipe" & "TZ350 exhaust":
a) http://www.perthstreetbikes.com/foru...01/index2.html
b) http://www.tz350.net/images/dyno_and...ms_reduced.jpg ..... from here : http://www.tz350.net/lcracer_article.htm
c) http://farm5.static.flickr.com/4063/...a6bc9533_o.jpg ........ from here : http://2stroker.createforumhosting.c...300-t3745.html
Hopefully, the c) is what you 're looking for.
edit: oh, you seek the G letter, so probably not.
Forum whore
BMEP: and why your not going to see any 12K rpm 30 hp FXR150's in F4
For those that missed it before BMEP is an important performance yardstick
http://www.epi-eng.com/piston_engine..._yardstick.htm
Brake Mean Effective Pressure (BMEP) is a very effective yardstick for comparing the performance of one engine to another, and for evaluating the reasonableness of performance claims or requirements.
The definition of BMEP is: the average (mean) pressure which, if imposed on the pistons uniformly from the top to the bottom of each power stroke, would produce the measured (brake) power output.
Note that BMEP is purely theoretical and has nothing to do with actual cylinder pressures. It is simply an effective comparison tool.
Brake Mean Effective Pressure (BMEP)
http://www.engineersedge.com/engine_...automotive.htm
4-Stroke BMEP = (HP x 13000)/(L x RPM)
2-Stroke BMEP = (HP x 6500)/(L x RPM)
L = Displacement in Liters i.e., 80 cc = .08 Liters 1 ci. = 16.39 cc
BMEP for those who missed it the first time .... and why 4-strokes are inherently limited and will eventually go the way of the dinosaurs.
BMEP for a FXR150 making 25 rwhp ... 28 crank hp at 12,000 rpm
4-Stroke BMEP = (HP x 13000)/(L x RPM)
BMEP = (28 x 13000)/(0.150 x 12,000)
BMEP = 364,000/1,800
BMEP = 202 psi for the FXR150 4 stroke.
BMEP for a GP125 making 30 rwhp ... 33 crank hp at 12,000 rpm
2-Stroke BMEP = (HP x 6500)/(L x RPM)
BMEP = (33 x 6,500)/(0.125 x 12,000)
BMEP = 214,500/1,500
BMEP = 143 psi for the GP125 2 stroke.
A BMEP of 200 to 220 psi is supposedly the upper practical limit for naturally aspirated engines and is only currently being achieved by the likes of F1 race engines.
At 202 psi for the FXR, the FXR150's do not have much more development potential left unless they are spun to 13 -14,000 rpm or more but at 12k rpm and 143 psi for the 2-stroke there is plenty of relatively easy potential left for the little Moto4 race bikes, and the writing is truly on the wall for the 4's.
And with things like direct cylinder injection making 2-strokes cleaner and inherently more powerful and cheaper than 4-strokes the 2 strokers must make a come back on the world stage at some point, its just shear economics.
http://www.allpar.com/neon/stroke.html Two-stroke engines have long been promising because of better fuel economy, fewer parts, better efficiency and a smaller engine package (about two-thirds the size and weight of conventional engines) that would allow for more design flexibility.
More on BMEP http://hpwizard.com/bmep.html and lots of other interesting formula like wind resistance.
No8 Wire Extraordinaire
ok lets do some simpler math
Litre road bike now pushing 170hp x0.15 (for 150cc) = 25.5hp
Developed to world super spec easy 200hp x 0.15 = 30hp.
But realistically, no way will reach that spec with FXR parts. Just want to poo in BMEP calculations.
Don't you look at my accountant.
He's the only one I've got.
Forum whore
What rpm is the world super spec 200hp engine spinning at.
I think TeeZee pointed out the FXR would have to spin to 13-14,000 rpm to make 30 crank hp and 30 was not going to happen at 12 which looks like their mechanical safe limit.
You might need to work through the math again as BMEP gives a true apples for apples comparison and indication of development potential, hp per liter does not.
No8 Wire Extraordinaire
As I said simpler math, the rpm assumption was yours. Perhaps a GSXR600 rod may help with the revs. Can't help out being a single, mind.
Heck with . . .actually why am I giving the 4 stroke guys ideas again??
Don't you look at my accountant.
He's the only one I've got.
Forum whore
Your simpler math is interesting but can be misleading unlike the BMEP rpm thing which points out where you have to goto to realisticly expect 30 crank hp from a FXR150 and its about 14,000 rpm, its not going to happen at 12K, the numbers don't lie they only revel the direction required, the realitive difficulty ahead and get you thinking about what may be required to get there.
Forum whore
a mate was telling me in japan they drag race fxr 150 and get 37hp at the rear wheel but thought about it , they must be useing nitro in them even though a better head with all the goodies just maybe you could with out nitro
Forum whore
BMEP for a FXR150 making 37 rwhp ... 40 crank hp at 14,500 rpm
4-Stroke BMEP = (HP x 13000)/(L x RPM)
BMEP = (40 x 13000)/(0.150 x 14,500)
BMEP = 520,000/2,175
BMEP = 239 psi for a FXR150 drag bike, that dosn't look impossible with a diet of meth and dash of nitro.
A better head, normally aspirated and 16,500 rpm still requires a BMEP of 210 so definatly a 37 rwhp FXR150 has to have chemical help like crazy man said or be bigger than 150cc.
See Dave, the BMEP concept is great for checking stuff out.
I posted this information about the BMEP concept in the true spirit of sharing and friendship
and the desire to depress the FXR boys before the GP at Taupo ....
Anorak
Looks like i need glasses 350 aye i will have another look.
this book has it i don't have this book but someone will
http://www.tz350.net/images/booksvid...nted_books.jpg
An extensive 350 page study of all Yamaha’s TD, TR, TA and TZ racers produced between 1959 and 1982.
125, 250, 350, 500, 700 and 750cc capacities, all models.
All changes between the models.
Over 200 b&w photos of bikes, components etc.
Portmaps and exhaust diagrams.
Full specification lists.
What each is like to own and ride.
Problems encountered with each model.
Serial number limits for every model.
How to identify each model from the others.
Plus a lot more!
http://www.tz350.net/yamaha_two_stro...otorcycles.htm
Kinky is using a feather. Perverted is using the whole chicken
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