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Discussion Starter · #1 ·
Quad hasn't had any new internals at all. Year and mods in signature. I am wanting to make some more power, but don't plan on going as radical as I intitially thought I would. Just looking for a nice powered quad, that runs off of pump gas still. Was going to do a bore and stroke, but realized, I'm almost satisfied with the performance now, and would rather have a good running sb/ss for longevity. I do plan to add a cdi and fci.

I want to run the best 12:1 or 12.5:1 piston, if it will indeed give me the most increase in power. Over say stock, or lower compression like 10.5:1 (or comparible ). Port and polish is a must. Just looking for the best piston to bring the most power out of sb/ss on pump gas.

Crank, probably go with stocker. Had plans to do the Falicon rod, trued n balanced to stock crank, but figured that would be overkill for a sb/ss. If I'm wrong, please let me know, because I am open to new suggestions.

With the build plans i currently have, i think stock valves and stock carb size should be fine, but again, if i can gain from a carb bore or bigger/better valves, please chime in.

The main reason I decided to stick with sb/ss was longevity. I'm not totally against a big bore, but is it worth the power gain to cash ratio, and how much longevity would I be sacrificing to do so? I'd rather go with one of MMAD's BB kits, vs. Athena for sure, but then I'd have to better valves, bored carb, ect. Which isn't a problem, cash wise, but is the power gain worth the cash vs my mild build plans? Also, how many hours of engine life would I be losing? I put a lot of money in my toys, but I take great care of them. Either build will have a clean filter, fresh oil at all times, etc. What I'm saying is, neglect won't play a role on engine life from my part.

FCI & Cdi will be added. New head bolts. Port and polish a must. Pending which route, upgraded valves... ect.

I trail ride, ride mx, and compete in 300ft dirt drags. Don't know where I am currently with mods, power wise, but want to squeeze the most I can out of this rebuild, yet still stay reliable. If great maintenance won't make a mild BB any less reliable, I dont mind going that route. Basically looking for strongest build I can get, that has the potential to last 400 hours or better. Any thoughts or opinions are welcome. Thanks in advance.
 

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Discussion Starter · #2 · (Edited)
Forgot about cams. Would a Webb cam with custom grind be better fit for BB, and over kill for SB 12.5:1? Thoughts?
 

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Discussion Starter · #3 ·
Is reaching for 60 hp with stock cams in modded position, really just reaching?
 

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Quad hasn't had any new internals at all. Year and mods in signature. I am wanting to make some more power, but don't plan on going as radical as I intitially thought I would. Just looking for a nice powered quad, that runs off of pump gas still. Was going to do a bore and stroke, but realized, I'm almost satisfied with the performance now, and would rather have a good running sb/ss for longevity. I do plan to add a cdi and fci.

I want to run the best 12:1 or 12.5:1 piston, if it will indeed give me the most increase in power. Over say stock, or lower compression like 10.5:1 (or comparible ). Port and polish is a must. Just looking for the best piston to bring the most power out of sb/ss on pump gas.

Crank, probably go with stocker. Had plans to do the Falicon rod, trued n balanced to stock crank, but figured that would be overkill for a sb/ss. If I'm wrong, please let me know, because I am open to new suggestions.

With the build plans i currently have, i think stock valves and stock carb size should be fine, but again, if i can gain from a carb bore or bigger/better valves, please chime in.

The main reason I decided to stick with sb/ss was longevity. I'm not totally against a big bore, but is it worth the power gain to cash ratio, and how much longevity would I be sacrificing to do so? I'd rather go with one of MMAD's BB kits, vs. Athena for sure, but then I'd have to better valves, bored carb, ect. Which isn't a problem, cash wise, but is the power gain worth the cash vs my mild build plans? Also, how many hours of engine life would I be losing? I put a lot of money in my toys, but I take great care of them. Either build will have a clean filter, fresh oil at all times, etc. What I'm saying is, neglect won't play a role on engine life from my part.

FCI & Cdi will be added. New head bolts. Port and polish a must. Pending which route, upgraded valves... ect.

I trail ride, ride mx, and compete in 300ft dirt drags. Don't know where I am currently with mods, power wise, but want to squeeze the most I can out of this rebuild, yet still stay reliable. If great maintenance won't make a mild BB any less reliable, I dont mind going that route. Basically looking for strongest build I can get, that has the potential to last 400 hours or better. Any thoughts or opinions are welcome. Thanks in advance.
For what you want a stock stroke using an oem crank would be a good reliable build. You could have your stocker sent out and rebuilt with a good rod and balanced to your piston also and it may be overkill but that crank will be stronger and hold up should you decide to upgrade later on. If your doing a piston and cylinder already imo i would go big bore. Stock cylinder honed or re-plated with a pump gas cp piston or one of mmads 97mm ready to run kits would be your cheapest option. Most people that have reliability issues either installed something wrong, used cheap parts or don't take care of their stuff and on a mild build like this you shouldn't have any issues. Std valve port job will be a good gain but you will definitely want to have the carb bored out as well or you wont see the power increase you should. I would talk to whoever you're going to have do the portwork and see what size carb they would recommend. I'd recommend Jeff @ Oregon Coast Powersports or Geoff @ Mmad, i've had great experiences using both. Cams I would stick with the stockers modded or add a warpspeed intake cam with the stock exhaust for a little more topend.
 

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Is reaching for 60 hp with stock cams in modded position, really just reaching?
It depends on the dyno but on the one we use it ain't happening unless its a real expensive big cc motor with stock cams in it for some reason OR certain expensive fuels are used... why would you spend $30 a gallon on fuel for a mild build though?
 

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Discussion Starter · #6 ·
For what you want a stock stroke using an oem crank would be a good reliable build. You could have your stocker sent out and rebuilt with a good rod and balanced to your piston also and it may be overkill but that crank will be stronger and hold up should you decide to upgrade later on. If your doing a piston and cylinder already imo i would go big bore. Stock cylinder honed or re-plated with a pump gas cp piston or one of mmads 97mm ready to run kits would be your cheapest option. Most people that have reliability issues either installed something wrong, used cheap parts or don't take care of their stuff and on a mild build like this you shouldn't have any issues. Std valve port job will be a good gain but you will definitely want to have the carb bored out as well or you wont see the power increase you should. I would talk to whoever you're going to have do the portwork and see what size carb they would recommend. I'd recommend Jeff @ Oregon Coast Powersports or Geoff @ Mmad, i've had great experiences using both. Cams I would stick with the stockers modded or add a warpspeed intake cam with the stock exhaust for a little more topend.
First and foremost, thank you for your input. I am a firm believer in buying right, not twice, so I want to plan, prep, write out, draw up, prep and write out again, before I even disassemble the motor. Anal, maybe, but it'll help me sleep better at night lol.

I was thinking of going with MMAD's 470 kit. I was looking at the cam shoot out dyno thread, (which I can't find anymore) and it seemed the stockers keep up well with the big names, and may have had more usable power at a few points through out the curve. Can't remember if the lightspeed or the warpspeed cams were involved though...

I'm not trying to go cheap on the build by any means, but it just seems that a lot of OEM stuff is great to work with i.e. cams, crank, valvetrain, etc.

Which leads me to my next question. Considering the stock crank is fine, should it be sent off to be rebuilt, get rod balanced & welded, or more cost effective to just buy new one, and do same thing?
 

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Discussion Starter · #7 ·
It depends on the dyno but on the one we use it ain't happening unless its a real expensive big cc motor with stock cams in it for some reason OR certain expensive fuels are used... why would you spend $30 a gallon on fuel for a mild build though?
I was just wondering if it were possible. Just curious. I know an aftermarket intake cam would get you there faster.
 

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Discussion Starter · #8 ·
Also I take it Warpspeed is a better cam than Lightspeed? From an exhaust cam standpoint I meant...
 

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Discussion Starter · #10 ·
What is a typical hour range that the bottom end on these motors may need a crank/rebuild?
Pends the mods and up keep, but my stock crank has to have 500 hours on it, and still going strong. I use a very good oil, and change it very often. My oil comes out the same color as it went in.
 
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