32cc stuffed crank

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Rep732

Rep732

The alchemist ☠️
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Im curious to know why is there nothing available for 32-34cc engines as far as stuffed cranks. I see they are available for smaller displacement engines and I've read they increase crankcase pressure which in turn give more compression in the cylinder.

Edit: I just seen king motors offer a 30mm stuffed crank but idk if I trust it
 
Seems your right, hard to find. I came up fruitless too... Maybe this is your chance to give a balanced crank a try?

BTW Gizmo has a full circle crank for the smaller motors. I really like that, prob last forever!
 
Hmmm:unsure: and @MonsterAir balanced crank? And show me this gizmo crank please :ROFLMAO:... from what I gather all that is done is just epoxy to make it fully "round". Sounds easy enough but I feel if not done right it could throw the crank off balance
 
That is a snazzy looking crank from gizmo. Too bad it won't work ?. And those obr cranks are cool but so them saying balanced and looking like that are ours unbalanced? Kinda hard to believe ours aren't atleast "checked"
 
They are so expensive I haven't run into anyone who has ran one. I think when they say balanced they mean shaped to have equal weight from side to side? I still need to learn more about them. Maybe one of us can call OBR and ask?
 
So first thing im curious about is why that much material is being machined off to be balanced? It seems like it contradicts the stuffed crank theory and if stuffed cranks truly worked i would think they would be in their engines. Im just trying to make sense of all this crank stuff on 2 strokes. ?‍♂️

Seems with these engines theres more than one way to skin a cat but since dynos are rare and skeptical with true power numbers how do we know what really makes more power or is just a waste of time and money
 
Only people who can truly tell are prob drag guys. I'd imagine when setup with timer to track speed and lap time you could know what's doing what...

I really want to put together a thread where we test certain setups and see what really is the best. Meaning create a set of rules and participants video their results, like I did with my marder but a little more thought out.


Your so right, we need a group to develop a quality dyno and have makers test on it not their own crap.
 
I like that idea . And from what I was reading about the stuffed cranks and case volume boils down to how you want the engine to respond in the low mid high range. And the exhaust design plays a big roll as well. I think this is beyond my ability especially if messing with case volumes lol
 
There are plenty of quality small engine dynos out there, the problem is they are very expensive for a hobbyist. The stiffest vs not stuffed crank is a debate as heated as oil. The factory cranks are typically balanced good enough for whatever most will do with them. They were designed for what we do, so not a major worry imo. Also stuffers arw normally some sort of plastic, or composite. I would say it also depends on engine design weather it makes a huge difference or not. I'll once again fall back to saws, because it's what I know best. The 555 husqy has 2 difference then a 562, no stuffer and slightly smaller transfer covers. It makes less power. Most have attributed this to lower speed air entering the cylinders, as they use identical cylinders, but that's mostly just assumptions. Even porting the 555 it falls short to a factory 562. Now a 359 (same displacement) ported comes very close to a stock 562, but the 562 still has the better cylinder design. Point being I wouldnt get too hung up on stuffers, if they arnt available it's because the engine builders decided it wasnt necessary, again imo.
 
I wonder how many people would pay to have their motors dyno'd? Seems like these machines are inbetween 5k-10k, judging off my quick search. @ $100 a pop that would only be 50-100 dyno tests and the amount of money I see spent on our hobby I think just maybe there is a business here somewhere.
 
MonsterAir said:
I wonder how many people would pay to have their motors dyno'd? Seems like these machines are inbetween 5k-10k, judging off my quick search. @ $100 a pop that would only be 50-100 dyno tests and the amount of money I see spent on our hobby I think just maybe there is a business here somewhere.
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...it'd cost me that here in uk to get one of me bikes dyno'd...?..an i hate payin that tbh....?....noway I'd pay that on one of me cars ☹....
my stuffed crank in my zen29..making it a 30.5cc now?
https://flic.kr/p/2hv4b4c
here u can see the stuffed bit...orange infilled bit
https://flic.kr/p/2hv6cXy
plus the rods longer obv...?
 
RcJunkie13 said:
Can someone plz explain what a stuffed crank is?
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Basically they fill in the circle with a plastic material which in turn makes less space in the crankcase. Sean explained it in his post.


Buyer beware!!!.... These do not last like a stock crank. From what I hear/understand the plastic will break down over time and/could mess up an engine. Only buying from reputable sources is recommended.
evssv said:
...it'd cost me that here in uk to get one of me bikes dyno'd...?..an i hate payin that tbh....?....noway I'd pay that on one of me cars ☹....
Click to expand...

Are you the type of guy with multiple cars/motors? Are they ported or upgraded besides $10 cranks? If you are why would you not consider spending $100 to see if your $600 motor is worth the expense? I ask because I'm interested in feedback on this idea.
 
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MonsterAir said:
Basically they fill in the circle with a plastic material which in turn makes less space in the crankcase. Sean explained it in his post.


Buyer beware!!!.... These do not last like a stock crank. From what I hear/understand the plastic will break down over time and/could mess up an engine. Only buying from reputable sources is recommended.


Are you the type of guy with multiple cars/motors? Are they ported or upgraded besides $10 cranks? If you are why would you not consider spending $100 to see if your $600 motor is worth the expense? I ask because I'm interested in feedback on this idea.
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yes..4x bikes...?4x 1/5th's....?...tbh I've never paid full price on my 2x nice engines..32sf pro and obr34v2.....yeah I'd like know there ture ? bhp obv.?...but not at £60-80 a pop....☹....
but my motorbikes r different ?
 
I have a stuffed cranked on my old 30.5 KM engine, its like a rubber material and I can confirm it does come away, I'll see if I can grab a picture in the morning. It's almost like silicone.
 
evssv said:
big bore kits r were its at bike wise?...I've gota 1300cc wisco bb kit to fit on my mk1 bandit1200...gonna b a beast.?
..well once i fix the gearbox it'll b☹?
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Damn !! I used to use Wiseco pistons all the time for rebuilds , 1300 CC wicked , remember the Hyabusa big motor ?? they built those into a race car for on road track racing with big wings . Cant remember the name ?? found it RADICAL car MONSTER
 
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