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Fullsizechevy9
08-07-2019, 04:40 PM
Is it possible? If so what do i do to turn a 12:1 piston into an 11.5:1? Or could i get away with buying say 5gal of 110 octane and mixing it with 5gal of 93 and using that with a 12:1 piston? I want to avoid 10.25:1 if i can so ill have a little more bottom end power.

El Camexican
08-07-2019, 07:29 PM
Is it possible? If so what do i do to turn a 12:1 piston into an 11.5:1? Or could i get away with buying say 5gal of 110 octane and mixing it with 5gal of 93 and using that with a 12:1 piston? I want to avoid 10.25:1 if i can so ill have a little more bottom end power.

Avoid the guess work, get a blank dome piston, have it cut to suit your needs. O-ring the cylinder to run wire and shoot for 220psi. Max. .025” clearances in all areas should get you where you need to be. I would also put a smaller exhaust valve in it and switch over to fiber reeds and a 2mm smaller carb. If you turn the bottom of your cylinder down you can enhance the port timing and advance cam timing all with one easy mod. You’ll also want to run a slightly cooler plug as well, try something that has an 11 or 12 on it, the letter don’t matter once you eclipse the 200psi barrier.

You can also get rid of all your valve lash as it robs power to have them closed for all that extra time and of course it goes without saying that Denco makes the best pipes for your application. Also get a 3/8” wire cable pull start rope and have your starter housing rope hole professionally bored out to suit and don’t forget to run 90% 114 VP fuel with 10% fingernail polish remover (acetone) and some sort of zddp enriched oil with lots of esters in it. I promise your bottom end might be better than stock and you won’t have to worry about running a 10.25:1 piston in that beast.

yaegerb
08-07-2019, 08:15 PM
Is it possible? If so what do i do to turn a 12:1 piston into an 11.5:1? Or could i get away with buying say 5gal of 110 octane and mixing it with 5gal of 93 and using that with a 12:1 piston? I want to avoid 10.25:1 if i can so ill have a little more bottom end power.

What you talkin’ bout Willis?

Fullsizechevy9
08-07-2019, 09:19 PM
I seen where mickey from 4 stroke tech was saying he takes a 12:1 piston and rounds the edges and makes it an 11:1 and runs it on pump gas. I am a machinist by trade he charges 200 for the piston, well i was hoping i could doit myself and save almost 100$. I want to be above 10.25:1 and still run pump gas or at least be able to buy race gas and mix it 50/50 with 93 octane. From what i gathered i will have a better low end above 10.25:1 if i could mix 50/50 110 or 120 with 93 octane and still be close to 12:1 that would be great.

Fullsizechevy9
08-07-2019, 09:27 PM
I have a 200s was thinking about getting a 2 stroke by time i mod this motor and barely reach 20hp i could probably buy a 250 2 stroke with around 40hp stock

Fullsizechevy9
08-07-2019, 09:38 PM
Was looking at used 250s on ebay for around $1000 i have also seen cr250 and crf450 for around $2500 the whole bike i may mod this motor some then start looking for a nice cr250 for a bike to trike conversion

Fullsizechevy9
08-07-2019, 10:23 PM
Is it a 200S ........or it could be a 200E ....series........or perhaps a 200ESSSS ....and you can convert it to a 2 stroke..........and den you can stroke it to work on 87 octane power piss..........and den buy a 259R stock not ported ........and den.......you can tie your mother down...........why ?My mother committed suicide

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Fullsizechevy9
08-07-2019, 10:44 PM
What a buzz kill ......I had to

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Fullsizechevy9
08-07-2019, 10:50 PM
What a buzz kill ......On the other hand a 250 2 stroke in a s frame would be a fun project i dont do any mx mainly a bunch of long stretches so any suspension i put on it would work prettu good i have a friend with a rm250 i could probably get cheap would take some frame mods dif motor mounts make it a double down tube instead of single would have to be able to fit the radiators in front the tank though or just make the bike a trike the frame is pretty beat up though i had to weld a bunch of spots that cracked for him and gusset a few spots got it as straight as i could

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yaegerb
08-07-2019, 11:03 PM
Is it possible? If so what do i do to turn a 12:1 piston into an 11.5:1?

You can recut the head to lower the compression



Or could i get away with buying say 5gal of 110 octane and mixing it with 5gal of 93 and using that with a 12:1 piston?

No. You need to run straight race gas for a high compression piston


I want to avoid 10.25:1 if i can so ill have a little more bottom end power.. Then buy a 12:1 and run VP 110

Fullsizechevy9
08-07-2019, 11:13 PM
You can recut the head to lower the compression




No. You need to run straight race gas for a high compression piston

Then buy a 12:1 and run VP 110If i get the compression around 11:1 would i be safe with pump gas like mickey is saying?

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Fullsizechevy9
08-07-2019, 11:15 PM
If i get the compression around 11:1 would i be safe with pump gas like mickey is saying?

Sent from my SAMSUNG-SM-N920A using TapatalkHe sells a 11:1 pump gas kit everybody seems to have a dif opinion on it you know so just trying to get everybodys opinion and find a happy medium

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El Camexican
08-07-2019, 11:16 PM
You can recut the head to lower the compression




No. You need to run straight race gas for a high compression piston

Then buy a 12:1 and run VP 110

Yep, yep, yep. Toss that 10.25 in and shave your head .020” to .030”, slot your cam gears to get the timing 2 degrees advanced of stock and you’ll have a strong runner that eats pump gas.

Fullsizechevy9
08-07-2019, 11:21 PM
Yep, yep, yep. Toss that 10.25 in and shave your head .020” to .030”, slot your cam gears to get the timing 2 degrees advanced of stock and you’ll have a strong runner that eats pump gas.10 4 thanks that sounds easier than messing with the piston i can mill the head at work on the bridgeport. Could i just slot my stock cam? And then use a timing light to advance it?

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Fullsizechevy9
08-07-2019, 11:23 PM
10 4 thanks that sounds easier than messing with the piston i can mill the head at work on the bridgeport. Could i just slot my stock cam? And then use a timing light to advance it?

Sent from my SAMSUNG-SM-N920A using TapatalkThinking of a .395 megacycles cam

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efhondakid
08-07-2019, 11:25 PM
Sweet baby Jesus. It’s a 2hunnit S. Stick the Wiseco hi comp piston in it, 10.25 or 10.5 what ever it is, an X cam and exhaust and be done with it. It’s not a race bike, trying to squeeze another half HP out of an S, you sound like you are trying to be the coolest kid at the retard table...

Fullsizechevy9
08-07-2019, 11:37 PM
Going from 12hp or so to upwards of 20hp is a pretty good gain for what it is to each their own its a pretty fun little bike if i could gain a good 30% or possibly more in power increase would make it that much better going to keep it might as well make it a runner i enjoy picking the smart ones brains and talking trikes you look like my handicap cousin by the way i beleive thats the correct term he rides the short bus

efhondakid
08-07-2019, 11:51 PM
The point I’m trying to make is that two bikes everything else even, you wouldn’t be able to tell the difference between one with an 11:1 piston or a 10.5:1 piston. For a race bike that has to have a half HP more than the next guy on the line, again all other things even, it barely matters still. Wanna feel a difference in the ass dyno? Do the X piston/cam/exhaust, it’s cheap and will wake up the plugged up S right up, best part, you can put any gas in it that you have sitting around and not have to worry about ordering VP for your hardtail. But, by all means, do continue to make assumptions of my knowledge.

Fullsizechevy9
08-08-2019, 12:00 AM
Just messing with you like i said earlier i value everybodys opinion and knowledge the more you learn the better which in turn will help me make the best decision on how i want my bike to run been seeing blasters for 7 to 900 been thinking about getting one and using the rear end and motor i would have suspension and around 20hp stock and could probably get it closer to 30hp by time im done with it so many ideas

Fullsizechevy9
08-08-2019, 12:02 AM
I even value my glamy

efhondakid
08-08-2019, 12:10 AM
The biggest issue with the 185/200S-X-XR is getting the flow out of the head, higher comp and longer duration/higher lift cam will only do so much if you can’t get the fuel in and exhaust out.

Fullsizechevy9
08-08-2019, 12:13 AM
I could get head work done bigger valves and port work i dont think the 86 x head with the bigger valves would go on my cylinder right

Fullsizechevy9
08-08-2019, 12:15 AM
Blaster may be my best option have more hp and rear suspension killing 2 birds with 1 pebble

El Camexican
08-08-2019, 12:34 AM
10 4 thanks that sounds easier than messing with the piston i can mill the head at work on the bridgeport. Could i just slot my stock cam? And then use a timing light to advance it?

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If you’re going to use a light to adjust your cam timing you’d better get an LED timing light as a conventional light can’t keep up with the smaller gears on these single cylinders.

Fullsizechevy9
08-08-2019, 12:40 AM
How would you go about advancing the timing? Do they make degreed sprockets for my application?

El Camexican
08-08-2019, 01:34 AM
Ok, seriously. To degree your cam(s) you need to buy, or more likely make slotted gears. A poor man can do it with a die grinder and a machinist can do it with an end mill. Search images on Google to see what they look like.

But before you even remove a gear off your cam you need to find out what Honda was shooting for originally (I doubt it’s in the manual), or what guys that have tuned these engines before recommend. Without this information you have no reason to begin the task.

Once you have base line numbers you’ll need a degree wheel, piston stop, a dial gauge and a method to mount it to the engine in a position that allows the dial gauge to follow the valves at the same angle as they travel in. It is recommended that the dial gauge has enough travel that it can remain in contact with the valve throughout the entire opening and closing cycle, but it’s not necessary.

The rest involves setting up the degree wheel (you might need an adapter) and a little math, but all this is on the Internet if you look.

Due to the different tolerances of all the parts that make up an engine few if any come with exactly the valve timing the designers intended, so this is a place to get some free power.

Rule of thumb is that retarding timing adds to top end power and advancing it adds to bottom end. A 2 degree change on a stock engine is safe, but more than that and you should consider checking valve to piston clearance, especially if you use an aftermarket piston.

Read up on the process and understand it before you put a wrench to the engine.

Fullsizechevy9
08-08-2019, 08:23 AM
Ok, seriously. To degree your cam(s) you need to buy, or more likely make slotted gears. A poor man can do it with a die grinder and a machinist can do it with an end mill. Search images on Google to see what they look like.

But before you even remove a gear off your cam you need to find out what Honda was shooting for originally (I doubt it’s in the manual), or what guys that have tuned these engines before recommend. Without this information you have no reason to begin the task.

Once you have base line numbers you’ll need a degree wheel, piston stop, a dial gauge and a method to mount it to the engine in a position that allows the dial gauge to follow the valves at the same angle as they travel in. It is recommended that the dial gauge has enough travel that it can remain in contact with the valve throughout the entire opening and closing cycle, but it’s not necessary.

The rest involves setting up the degree wheel (you might need an adapter) and a little math, but all this is on the Internet if you look.

Due to the different tolerances of all the parts that make up an engine few if any come with exactly the valve timing the designers intended, so this is a place to get some free power.

Rule of thumb is that retarding timing adds to top end power and advancing it adds to bottom end. A 2 degree change on a stock engine is safe, but more than that and you should consider checking valve to piston clearance, especially if you use an aftermarket piston.

Read up on the process and understand it before you put a wrench to the engine.Sounds good i will start reading all i can on the subject

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Shep1970
08-08-2019, 08:47 AM
I could get head work done bigger valves and port work i dont think the 86 x head with the bigger valves would go on my cylinder right

If your question is if the 86 200x head will fit. No it’s not even close, very different. This’ll be my only response in this thread except my opinion is just save your coin and buy a 250r/350x.

Shep

Fullsizechevy9
08-08-2019, 11:27 AM
Theres my girl i missed you

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Fullsizechevy9
08-08-2019, 12:25 PM
I think thats what im going to do banshee in 250r frame with twin drag pipes sticking 3 feet out each side for my girl glamy to sit on :Bounce

Fullsizechevy9
08-08-2019, 12:27 PM
Bounce bounce bounce fart:Bounce:naughty::naughty::lol:

Fullsizechevy9
08-08-2019, 01:27 PM
.............watch me mommy watch me !...........i got my own sh!t .........Fullsizefeckinretard ...........i don`t wonder what it`s "like" to defy gravity.........i do it any time i want at Mother G............lick my salad ! :Bounce:rolleyes::Bounce:rolleyes::Bounce:rolleyes ::Bounce:rolleyes::Bounce:rolleyes::Bounce:rolleye s::Bounce:rolleyes::Bounce:rolleyes:Your my idol glamy i want to be just like you someday i love you buddy

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Fullsizechevy9
08-08-2019, 01:32 PM
All hail the trike god hes better on his knees than he is on three:postwhoreairfooler

Fullsizechevy9
08-08-2019, 01:34 PM
I can show you how to defy gravity with your legs behind your head:Bounce:naughty: