alx.cruz
Super Veteran
with the above explanation, I think the poly quad design is better on DOHC engines such as Suzuki Raider 150...
because it has no rocker arm and because of cams can be made/regrinded not to open/close at the same time...
200cc - Which Would You Choose
- Thread starter HKholic
- Start date
because it has no rocker arm and because of cams can be made/regrinded not to open/close at the same time...
docgabby
Super Veteran
IS YOUR CYLINDER BORE AT MAXIMUM SIZE?
A LARGER BORE IS FAR MORE CAPABLE IN SEARCH OF ADDITIONAL POWER. IT HAS BEEN PROVEN TIME AND AGAIN THAT A BIGGER BORE PERMITS MORE AIRFLOW BY ALLOWING ADDITIONAL SPACE FOR AIR/FUEL TO GET PAST THE VALVES THRU LESS CYLINDER WALL TO VALVE INTERFERENCE OR SHROUDING.
THIS BEING SAID ONE MUST NOT FAIL TO MAKE SURE COMPARISONS ARE DONE WITH BIG VS. SMALL BORE BY MAKING "SURE" THE CC OR CID ARE THE SAME OR VERY CLOSE!
I STATED THE OBVIOUS HERE BECAUSE I HAVE SEEN COMPARISONS WHERE THE OTHER ENGINE IS 25-50cc's LARGER OR IN THE CASE OF V-8'S HAVING 25-50+ CUBIC INCHES MORE!!!
AGAIN LOOK AT MY NEXT ARTICLE TO THIS HERE, WHERE I COMPARE DIFFERENT BORE AND STROKE CONFIGURATIONS WHILE HAVING THE SAME BASIC ENGINE DISPLACEMENT.....
I had to stress this point because I saw one example where the bigger bore lost to the smaller bore engine because it had a lot more stroke, the old rule here is> "There is no replacement for displacement or CC's" here it is very true!
However on the other spectrum a bigger bore will lose to a small bore if the intake airflow is restricted somewhat, to the point the additional breathing capability is negated by this airflow restrictions.....
SO WHERE IS THE LIMIT TO BORING THE CYLINDERS?
WELL THERE ARE MANY FACTORS TO BE CONSIDERED AND SINCE THERE ARE MANY DIFFERENT TYPES OF ENGINES, WE WILL FOR THE SAKE OF COMPARISON USE THE TYPICAL AMERICAN BUILT V-8'S MAXIMUM BORE SPECIFICATIONS AND DOWNSIZE THIS AND APPLY THE SAME CRITERIA FOR ANY MOTORCYCLE OR SMALL DISPLACEMENT ENGINE......
HOW BIG IS TOO BIG?
A STOCK BORE AS IT COMES FROM THE FACTORY HAS MORE THAN ENOUGH MATERIAL THAT "SOAKS-UP" HEAT GENERATED BY THE COMBUSTION PROCESS.
ADDITIONALLY THE FORCES EXERTED INSIDE THE CYLINDERS WILL TRY TO DISTORT,CRACK, EXPAND AND WARP THE CYLINDERS TO THE DETRIMENT OF POWER PRODUCTION!
SO WHEN THE MATERIAL IS THICK ENOUGH, THE ABOVE POSSIBILITIES ARE SIGNIFICANTLY REDUCED OR ELIMINATED ENTIRELY WITHIN REASONABLE EXPECTATIONS.
ON THE OTHER HAND, IF THE CYLINDER WALL IS INSUFFICIENTLY THIN, THE ABILITY TO SPREAD AND SOAK UP HEAT IS FURTHER COMPROMISED AND ENGINE RELIABILITY, PISTON RING LIFE WILL BE SERIOUSLY AFFECTED BY THE HOTTER AND OR OVERHEATING CYLINDER.
(You can further test this theory by torching the sharp end of a blade/knife and seeing the edges start to glow orange and warpage will result. If applying the same heat towards the blunt or opposite side of the same blade, you will notice the thicker edge will not glow as readily and will have less chance of warping....)
RING SEAL INTEGRITY:
ANOTHER IMPORTANT FACTOR IS RING SEAL INTEGRITY. WE ALL KNOW THAT IF THE CYLINDER WALL IS THIN, THE POSSIBILITIES OF FLEXING GOES UP THE THINNER THE WALL!
EVENTUALLY THE CYLINDER CANNOT MAINTAIN A "RADIALLY ACCURATE" OR A "PERFECTLY ROUND" SHAPE TO PROPERLY SEAL THE RINGS OF COMBUSTION PRESSURES FROM GETTING BY.....
I DO NOT KNOW OF ANYONE CAPABLE OF MAKING POWER WHEN THE CYLINDER IS OUT OF ROUND EVEN BY S SMALL AMOUNT AND THEREFORE EXCESSIVE BLOW-BY WILL RESULT!
THE CYLINDER THRUST SIDE:
THIS IS VERY IMPORTANT!
CYLINDERS THAT ARE BEING CONSIDERED FOR SERIOUS OVERBORE, ONE MUST TAKE INTO ACCOUNT THE "THRUST SIDE" OF THE CYLINDERS !"
THIS MUST" BE ADDRESSED BY THE RACING ENGINE BUILDER!
WHERE IS THE THRUST SIDE OF ANY CYLINDER???
IT IS THE SIDE THAT WEARS OUT MORE AND HAS THE CHANCE OF CRACKING IF IT IS THIN!
THE THRUST SIDE IS USUALLY THE SIDE WHERE THE CRANKSHAFT IS TURNING ITS DIRECTION TO>
AND WILL LOAD THE PISTON AND ROD TO BE DISPROPORTIONATELY "SHOVED" ON 1 SIDE ONLY!
THIS SIDE IS WHERE MOST OF THE BORE WEAR OCCURS!
An example here is when you look at a motorcycle engines from the "left side" and the engine is rotating in a counterclockwise direction?
The Thrust side of the cylinder is the front part or the front facing side nearest the front tire!
If it is turning clockwise? The cylinder section nearest the rear tire is the thrust side.
On a typical V-8 engine, rotating on a clockwise direction viewed from the front. The thrust side on the passenger side or right bank is towards the center of the block or camshaft. The thrust side on the driver or left side is towards the exhaust manifold side.
THE THRUST SIDE ON A TYPICAL V-8 "MUST" NOT OR NEVER BE THINNER THAN .150-.160!
IF IT IS THICKER HERE IT IS BETTER.....
ANY THINNER AND THE CYLINDER WILL NOT BE ABLE TO CONTAIN THE COMBUSTION PRESSURES AND BORE DISTORTION WILL RESULT AND LOSS OF POWER IS THE NET EFFECT.
"SONIC CHECK" THE FULL LENGTH OF THE CYLINDER AND RECORD THE INFO!
PAYING ABSOLUTE ATTENTION TO THE THRUST SECTION THICKNESS!
THIS WILL GIVE YOU A GOOD INSIGHT INTO THE OVERBORE CAPABILITY OF ANY BLOCK IN YOUR ARSENNAL!
ON ANY MOTORCYCLE OR SMALL DISPLACEMENT ENGINE? CONSULT THE CYLINDER MANUFACTURER AT THE MAXIMUM OVERBORE AND MINIMUM THICKNESS ALLOWABLE!
IF I HAVE TO GUESS HERE MAYBE .100 OR MORE AND NEVER LESS.....
ANOTHER CONCERN THAT MUST BE LOOKED INTO IS THE "INCREASED SIDE LOADING" PRESENT WITH ANY STROKER ENGINES WITH A SHORT ROD TO STROKE RATIO!!!
WHEN CHECKING THE BORE DIAMETER THIS IS MOST EVIDENT WHEN THE BOTTOM OF THE BORE IS OUT OF ROUND OR EGG SHAPE.....
THIS IS EVIDENCE OF EXCESSIVE SIDE LOADING....
AND!!!
ANY SERIOUS ENGINE BUILDER "MUST" CHECK THE PISTON TRAVEL AT THE BOTTOM OF THE CYLINDER!
THE PISTON SKIRT MUST NOT TRAVEL TOO FAR "BELOW" THE BOTTOM OF THE CYLINDER LINER WHEN STROKING THE CRANK....
Many times I have seen instances where the piston is about to come out of the bottom of the cylinder at "BDC" and seem to wobble and come out at this point and is nothing but a time bomb!
AGAIN THERE ARE LIMITS TO CYLINDER OVERBORING & STROKING>
DICTATED BY MATERIAL THICKNESS AND CYLINDER LENGTH!
HORSEPOWER TIP:
SINGLE CYLINDER & SOME INLINE ENGINES.
WHEN BORING A CYLINDER TO MAXIMUM AND AVOIDING THE PITFALLS OF A THIN CYLINDER WALL SPECIALLY ON THE "THRUST SIDES?
OFFSET BORING! BY MACHINING & CUTTING LESS FROM THE THRUST SIDES AND RELYING MOST OF THE CUTTING ON THE OPPOSITE SIDE OF THE CYLINDER. THE EFFECT IS HAVING MORE MATERIAL WHERE IT COUNTS>THRUST SECTION WHERE MORE OF THE PISTON SCUFFING/RUBBING IS HIGHER THAN ON THE OPPOSITE SIDES.
THE ONLY CAUTION HERE IS TO MAKE SURE ROD/PISTON ALIGNMENT IS NOT ADVERSELY AFFECTED TOO MUCH BY THIS PROCEDURE.....
OFFSETTING THE MOUNTING BOLT HOLES WILL ALSO HELP IF MISALIGNMENT IS TOO MUCH.
BEN ALAMEDA @ PARA TECH. FB, BENALAMEDARACING.COM
A LARGER BORE IS FAR MORE CAPABLE IN SEARCH OF ADDITIONAL POWER. IT HAS BEEN PROVEN TIME AND AGAIN THAT A BIGGER BORE PERMITS MORE AIRFLOW BY ALLOWING ADDITIONAL SPACE FOR AIR/FUEL TO GET PAST THE VALVES THRU LESS CYLINDER WALL TO VALVE INTERFERENCE OR SHROUDING.
THIS BEING SAID ONE MUST NOT FAIL TO MAKE SURE COMPARISONS ARE DONE WITH BIG VS. SMALL BORE BY MAKING "SURE" THE CC OR CID ARE THE SAME OR VERY CLOSE!
I STATED THE OBVIOUS HERE BECAUSE I HAVE SEEN COMPARISONS WHERE THE OTHER ENGINE IS 25-50cc's LARGER OR IN THE CASE OF V-8'S HAVING 25-50+ CUBIC INCHES MORE!!!
AGAIN LOOK AT MY NEXT ARTICLE TO THIS HERE, WHERE I COMPARE DIFFERENT BORE AND STROKE CONFIGURATIONS WHILE HAVING THE SAME BASIC ENGINE DISPLACEMENT.....
I had to stress this point because I saw one example where the bigger bore lost to the smaller bore engine because it had a lot more stroke, the old rule here is> "There is no replacement for displacement or CC's" here it is very true!
However on the other spectrum a bigger bore will lose to a small bore if the intake airflow is restricted somewhat, to the point the additional breathing capability is negated by this airflow restrictions.....
SO WHERE IS THE LIMIT TO BORING THE CYLINDERS?
WELL THERE ARE MANY FACTORS TO BE CONSIDERED AND SINCE THERE ARE MANY DIFFERENT TYPES OF ENGINES, WE WILL FOR THE SAKE OF COMPARISON USE THE TYPICAL AMERICAN BUILT V-8'S MAXIMUM BORE SPECIFICATIONS AND DOWNSIZE THIS AND APPLY THE SAME CRITERIA FOR ANY MOTORCYCLE OR SMALL DISPLACEMENT ENGINE......
HOW BIG IS TOO BIG?
A STOCK BORE AS IT COMES FROM THE FACTORY HAS MORE THAN ENOUGH MATERIAL THAT "SOAKS-UP" HEAT GENERATED BY THE COMBUSTION PROCESS.
ADDITIONALLY THE FORCES EXERTED INSIDE THE CYLINDERS WILL TRY TO DISTORT,CRACK, EXPAND AND WARP THE CYLINDERS TO THE DETRIMENT OF POWER PRODUCTION!
SO WHEN THE MATERIAL IS THICK ENOUGH, THE ABOVE POSSIBILITIES ARE SIGNIFICANTLY REDUCED OR ELIMINATED ENTIRELY WITHIN REASONABLE EXPECTATIONS.
ON THE OTHER HAND, IF THE CYLINDER WALL IS INSUFFICIENTLY THIN, THE ABILITY TO SPREAD AND SOAK UP HEAT IS FURTHER COMPROMISED AND ENGINE RELIABILITY, PISTON RING LIFE WILL BE SERIOUSLY AFFECTED BY THE HOTTER AND OR OVERHEATING CYLINDER.
(You can further test this theory by torching the sharp end of a blade/knife and seeing the edges start to glow orange and warpage will result. If applying the same heat towards the blunt or opposite side of the same blade, you will notice the thicker edge will not glow as readily and will have less chance of warping....)
RING SEAL INTEGRITY:
ANOTHER IMPORTANT FACTOR IS RING SEAL INTEGRITY. WE ALL KNOW THAT IF THE CYLINDER WALL IS THIN, THE POSSIBILITIES OF FLEXING GOES UP THE THINNER THE WALL!
EVENTUALLY THE CYLINDER CANNOT MAINTAIN A "RADIALLY ACCURATE" OR A "PERFECTLY ROUND" SHAPE TO PROPERLY SEAL THE RINGS OF COMBUSTION PRESSURES FROM GETTING BY.....
I DO NOT KNOW OF ANYONE CAPABLE OF MAKING POWER WHEN THE CYLINDER IS OUT OF ROUND EVEN BY S SMALL AMOUNT AND THEREFORE EXCESSIVE BLOW-BY WILL RESULT!
THE CYLINDER THRUST SIDE:
THIS IS VERY IMPORTANT!
CYLINDERS THAT ARE BEING CONSIDERED FOR SERIOUS OVERBORE, ONE MUST TAKE INTO ACCOUNT THE "THRUST SIDE" OF THE CYLINDERS !"
THIS MUST" BE ADDRESSED BY THE RACING ENGINE BUILDER!
WHERE IS THE THRUST SIDE OF ANY CYLINDER???
IT IS THE SIDE THAT WEARS OUT MORE AND HAS THE CHANCE OF CRACKING IF IT IS THIN!
THE THRUST SIDE IS USUALLY THE SIDE WHERE THE CRANKSHAFT IS TURNING ITS DIRECTION TO>
AND WILL LOAD THE PISTON AND ROD TO BE DISPROPORTIONATELY "SHOVED" ON 1 SIDE ONLY!
THIS SIDE IS WHERE MOST OF THE BORE WEAR OCCURS!
An example here is when you look at a motorcycle engines from the "left side" and the engine is rotating in a counterclockwise direction?
The Thrust side of the cylinder is the front part or the front facing side nearest the front tire!
If it is turning clockwise? The cylinder section nearest the rear tire is the thrust side.
On a typical V-8 engine, rotating on a clockwise direction viewed from the front. The thrust side on the passenger side or right bank is towards the center of the block or camshaft. The thrust side on the driver or left side is towards the exhaust manifold side.
THE THRUST SIDE ON A TYPICAL V-8 "MUST" NOT OR NEVER BE THINNER THAN .150-.160!
IF IT IS THICKER HERE IT IS BETTER.....
ANY THINNER AND THE CYLINDER WILL NOT BE ABLE TO CONTAIN THE COMBUSTION PRESSURES AND BORE DISTORTION WILL RESULT AND LOSS OF POWER IS THE NET EFFECT.
"SONIC CHECK" THE FULL LENGTH OF THE CYLINDER AND RECORD THE INFO!
PAYING ABSOLUTE ATTENTION TO THE THRUST SECTION THICKNESS!
THIS WILL GIVE YOU A GOOD INSIGHT INTO THE OVERBORE CAPABILITY OF ANY BLOCK IN YOUR ARSENNAL!
ON ANY MOTORCYCLE OR SMALL DISPLACEMENT ENGINE? CONSULT THE CYLINDER MANUFACTURER AT THE MAXIMUM OVERBORE AND MINIMUM THICKNESS ALLOWABLE!
IF I HAVE TO GUESS HERE MAYBE .100 OR MORE AND NEVER LESS.....
ANOTHER CONCERN THAT MUST BE LOOKED INTO IS THE "INCREASED SIDE LOADING" PRESENT WITH ANY STROKER ENGINES WITH A SHORT ROD TO STROKE RATIO!!!
WHEN CHECKING THE BORE DIAMETER THIS IS MOST EVIDENT WHEN THE BOTTOM OF THE BORE IS OUT OF ROUND OR EGG SHAPE.....
THIS IS EVIDENCE OF EXCESSIVE SIDE LOADING....
AND!!!
ANY SERIOUS ENGINE BUILDER "MUST" CHECK THE PISTON TRAVEL AT THE BOTTOM OF THE CYLINDER!
THE PISTON SKIRT MUST NOT TRAVEL TOO FAR "BELOW" THE BOTTOM OF THE CYLINDER LINER WHEN STROKING THE CRANK....
Many times I have seen instances where the piston is about to come out of the bottom of the cylinder at "BDC" and seem to wobble and come out at this point and is nothing but a time bomb!
AGAIN THERE ARE LIMITS TO CYLINDER OVERBORING & STROKING>
DICTATED BY MATERIAL THICKNESS AND CYLINDER LENGTH!
HORSEPOWER TIP:
SINGLE CYLINDER & SOME INLINE ENGINES.
WHEN BORING A CYLINDER TO MAXIMUM AND AVOIDING THE PITFALLS OF A THIN CYLINDER WALL SPECIALLY ON THE "THRUST SIDES?
OFFSET BORING! BY MACHINING & CUTTING LESS FROM THE THRUST SIDES AND RELYING MOST OF THE CUTTING ON THE OPPOSITE SIDE OF THE CYLINDER. THE EFFECT IS HAVING MORE MATERIAL WHERE IT COUNTS>THRUST SECTION WHERE MORE OF THE PISTON SCUFFING/RUBBING IS HIGHER THAN ON THE OPPOSITE SIDES.
THE ONLY CAUTION HERE IS TO MAKE SURE ROD/PISTON ALIGNMENT IS NOT ADVERSELY AFFECTED TOO MUCH BY THIS PROCEDURE.....
OFFSETTING THE MOUNTING BOLT HOLES WILL ALSO HELP IF MISALIGNMENT IS TOO MUCH.
BEN ALAMEDA @ PARA TECH. FB, BENALAMEDARACING.COM
docgabby
Super Veteran
Always a wealth of knowledge Doc! With that being said, I am comfortable with the route I have chosen. Besides, it is very close to your commuter set-up.
sniping_area
Super Veteran
wow modifikasi
sniping_area
Super Veteran
more pics?Let the fun begin! Saying goodbye to my Uma block, but welcome my Malossi block married with a stroker crank.
View attachment 19338
sniping_area
Super Veteran
precision
HKholic
Member
204cc
Well, the beast is finished. I can honestly say that a stroker crank was the right choice........for me. Bike has loads of torque now. 1st, 2nd and 3rd gear go quick. Thinking of changing to 15/39 gearing. And wow!! The exhaust note is mean now. Deeper, louder and is a giveaway that the bike ain't stock. Now I will sit back and enjoy the moto for a while...........at least until something else comes out that I need to have. Thanks to all that helped me along the way: traxxas-modifier , haen , docgabby , axon and to all that contributed to this thread. A lot of knowledge in this here forum and excellent source for parts. 
Well, the beast is finished. I can honestly say that a stroker crank was the right choice........for me. Bike has loads of torque now. 1st, 2nd and 3rd gear go quick. Thinking of changing to 15/39 gearing. And wow!! The exhaust note is mean now. Deeper, louder and is a giveaway that the bike ain't stock. Now I will sit back and enjoy the moto for a while...........at least until something else comes out that I need to have
. Thanks to all that helped me along the way: traxxas-modifier , haen , docgabby , axon and to all that contributed to this thread. A lot of knowledge in this here forum and excellent source for parts.
sniping_area
Super Veteran
bravo superb!
your welcome bro.204cc
Well, the beast is finished. I can honestly say that a stroker crank was the right choice........for me. Bike has loads of torque now. 1st, 2nd and 3rd gear go quick. Thinking of changing to 15/39 gearing. And wow!! The exhaust note is mean now. Deeper, louder and is a giveaway that the bike ain't stock. Now I will sit back and enjoy the moto for a while...........at least until something else comes out that I need to have
whats now your updated final mods specs? please list
HKholic
Member
Gladly broyour welcome bro.
whats now your updated final mods specs? please list
Malossi 63mm
Faito 3.5mm Jack-up w/4mm block spacer
23/20 ported head
APPI valve springs
Faito Turbo cam
TM28 carb
K&N pod
BRT Neo Dual band
AHM M1 w/Akrapovic carbon muffler
15/39 gearing
Stock tires
Super lightweight Antigravity battery(9ah)
sniping_area
Super Veteran
xclickclickx
Veteran
Haen,update for the result of 66mm forged piston, polyquad cyl head 23-21 IN, 18-19 EX... 29.64 PS...
previous result using 22/19 standard big valve 180 cc is 22.34 PS only..
would you mind letting me know more about your 66mm bore did you re-sleeve a cylinder or is there a kit you could let me know about?
curious to know what the compression and the temperature was if you could?? just even a brief description if you dont have the numbers.
By the way thanks for the mapping very interesting loving your work!!
Cesar Ablao
Super Veteran
Good day doc! Im just wondering, are you using the lhk head with raider valves sir? How abt. the springs sir?
docgabby
Super Veteran
i use hispeed valve springs.