I AM BACK!! WAHAHAHAHA....TIM your lc done d? KRZ dim?

thanks for your input alexei and thianz,

i have decided to turn down the deal because there's too many thins to be concern about.

Ahaha, thanks for adding me in FB. Congrats on your new job.
KRZ rim is 18 inch rear, right?

Remember come Penang find me go makan angin 11k RPM.
This year want go MotoGP Sepang?

Personally, if interested in 2nd hand bike, can consider 2-lejang.
I have 3 bikes, all senang jaga.

Alexei, yesterday I run a simulation on the bore x stroke of 135LC. It seems engine will start to have minor reliability issue above 9700rpm, and the conrod easily spoilt if go beyond 11000rpm.

From real world experience, I do notice engine vibration near 10krpm on 3rd gear. I think in order to rev above 10k smoothly, need shorter stroke like TZM or KIPS (54mm / 54.4mm). LC135 is 58.7mm.

Seems that Yamaha set the rev cut at 9200rpm for a reason.

charge-n-goTry check RGV stroke length... 49mm

This post has been edited by alexei: Jun 10 2015, 09:42 PM

yup, in fact most of the pro engine tuners prefer to have short stroke and bigger bore. Reason is simple, higher rev and able to accomodate bigger valves. jackrod kit is good in a way to make engine feel more torquey at lower rev (higher momentum). Good for daily usage, but bad for racing application. Another benefit of long stroke engine is lower weight and material used compare to bigger bore of the same cc. For the sake of cost saving and fc, many car manufacturers go for long stroke, but it is not so good for bike which needs to rev high to gain power.

Nice link there, that simulation just show some color and some reliability number without giving the exact figure like 3.5kft/min, waiting for your 200km tips also. omg

http://www.automationgame.com/about/
screenshot one of the engine design interface here.
on the right, got some green logo, such as piston, conrod, knocking and etc. when turn into slight yellow, means slight reliability issue (reliability number will reflect), then it will start to turn yellow, orange and finally red.

This post has been edited by charge-n-go: Jun 10 2015, 09:15 PM

charge-n-goLooks fun enough to understand the gist, but is it detailed enough to be practical?
Even conrod length affects the engine performance, and requires a different cam profile.
Same goes to piston and crankshaft offset, etc. If I go on and on, I'd never be able to design anything at all. LOL.

About the 4000 ft per minute, it's a bit common. Google it and see.

For the 200km per 4.x liter trick, same as I told you when we last met. On the RGV, I removed all gasket and just used Bardahl RTV gasket and left overnight to cure... This penalizes both intake and exhaust port timing a little bit, but significantly increased the compression ratio.

This post has been edited by alexei: Jun 10 2015, 09:47 PM

definitely not detail enough, just some big picture of how an engine is designed.
1st tab is to choose engine type: Inline4, Inline6, V8, etc. Then head technology, such as OHV, SOHC, DOHC etc, and also number of valves per cylinder - 2, 3, 4, 5. Besides, also can choose material, such as cast iron, alu, alsi, magnesium.

2nd tab... crank material, conrod material, piston type (in the image)

3rd tab... compression ratio, camshaft profile (too bad no lift), VVTi option (no, intake only, intake+exhaust), VVTL option.

4th tab... NA or Turbo. If turbo, unlock the choices of intercooler type, compressor size, turbine size, A/R ratio, and boost level

5th tab... fuel system and intake: carburetor - single, dual, quad or DCOE; injector: mecha, single, multi, direct. Intake type: single, dual (for V8), individual TB; standard, perf or race intake, AF ratio, ignition timing.

6th tab... exhaust system: type of header - cast, short, tubular, long tubular, race tubular; overall diameter; cat converter; muffler #1 and #2 type.

7th tab... engine test : power/torque/fuel economy/boost curve across the rpm, and diagnose which engine part is more prone to reliability issue.


Yup, although it is a big picture, enough variable to play with. Too much into detail, we need a team of engineers, LOL

charge-n-goyou're getting a good engine? Not sure if mine can beat yours.

Tonight got things to play with! I simulator the kips!!!

Sometime i also think the same way with you. Cause what i know is shorter stroke can rev more. But long stroke will having more accerlation in low rpm. Just my cent but i saw suzuki belang and fx125 hv a very short stroke but bigger block.

alexei,
For daily usage engine, I am more fond of getting a flat torque curve at midrange than max bhp, and at least 80% of the max torque available at 2000rpm for good drivability.
For street-racing / touge engine, will go for 7500 - 8000rpm range, flat torque curve at midrange too, and at least 80% of the max torque available at 3000rpm.
For track-racing, 9000rpm above, sacrifice low-rpm torque for good mid to mid-high rpm torque. more power is better
It's fun to design various engine, and put it into a car to check the mileage. Different gearing also affect FC a lot. Adding a turbo also changed the characteristic, and increased the service cost too.
ahh, just too much, lol.

enjoy dude !

0163119779
actually i do think, decreasing stroke lower the compression ratio quite a lot. must get a high dome piston to compensate. shorten by 2mm (from 58.7mm to 56.7mm) is a good start. maybe extra 500rpm.

but problem where have rod around 56mm can put in lc? What i calculate this way..
57mm fz block n forged normal piston. (Fz piston compression quite low)
56mm rod (let said la)
can make around 142 cc and i feel safe with that la...Haha

For Diasil block better not use forged piston. Just use cast one, consistent performance.

If i can found 55mm rod i still have 1 issue the the block height....kena potong block...haha

Actually 135LC comes with Forged piston as standard.


yes, block height. that's what I mean by compression lost. If potong block, the head will be lowered, dont know still can mount nicely on the chasis or not

make jack rod foundry in hatyai, make head big valve only rm380 with copper gasket. jack rod big diameter 110 only 390 lhk forged rod. 126mm. need wait one month


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Nowadays I TT everyday lunch time with TZM. Anyone want to meet up during lunch time can ping me.

PJ? haha