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Old 09-28-2010, 04:59 AM
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BarelyAWake BarelyAWake is offline
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Default Re: Zoombicycles 80cc slant head

The reviews are mixed to say the least, often impressed at first it seems casting flaws & warpage are somewhat commonplace with people changing their minds about their benefits and general quality later in the thread...

It'd be nice if someone posted some hard data via a before & after w/a comp gauge, while it appears they do actually have a squish band - how much is the compression really increased by? Is it worth maintaining a part reported by many to be problematic when decking a stock head might achieve the same results?

It's prolly best to get one for yourself if you're interested as there's no clear consensus at all regarding this product - much like the engines they're attached to it's most likely a "luck of the draw" thing with a touch of personal preference thrown in lol
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Old 09-28-2010, 10:50 AM
DudeZXT DudeZXT is offline
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Default Re: Zoombicycles 80cc slant head

Originally Posted by Goat Herder View Post
I ran regular pump fuel in my Bike comparison . The guy running neck and neck with me was running race fuel by the way. [higher octane]

Something else to think about when you run a higher compression head guy's. The guy running the slant head that could give me comp has a brass bushing now. He threw a roller cage.

All this said the motors from china are kits in them selves. A guy's best bet for longevity is to keep it simple lower compression head.
Has there been any conclusive data about different octane gases used in these causing differences in engine performance?

I'm with you about the ports. I read the thread about porting and decided to do it on my 2nd install. I was pleasantly surprised to see that I didn't have much at all to do to clean up the ports on the Zoom 66/80..

My brother-in-law was doing about 22 on a completely stock slant and I figured that's pretty impressive for his weight. He tells me that he's 300 even, but my wife says there's no way ~ probably 360...
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Old 09-28-2010, 10:55 AM
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bairdco bairdco is offline
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Default Re: Zoombicycles 80cc slant head

Originally Posted by MotorNut123 View Post
12 pack?? What is it?

and now that i think about it, 12 beers are a lot like a slant head. it sounds like a great idea to drink them all, it's fun, and it makes you think everything is so much better, and then the next day you realize it wasn't the greatest idea afterall.

and, you'll never admit to it, because drinking is so much fun, you continue to do it, even though in the long run, it's destroying your body. but who cares, right? for what goatherder said, you kinda lost me. while weight may make a difference in a race between two people, individually it doesn't matter. just because i'm 135lbs doesn't mean i can't tell the difference between a fast bike and a slow one.

now for my final opinion on this subject...

i find the name "slant head" for a chinese product very offensive.
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Old 09-28-2010, 01:31 PM
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Goat Herder Goat Herder is offline
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Default Re: Zoombicycles 80cc slant head

You lost me there I don't drink.

Yes there is a night and day difference with longevity on a bike and all its parts when a guy weighs less. Nothing breaks.

I am at a pro wrestler build over 6 foot tall. I have also peddled a bike without a motor on it the last two weeks to a easy sum of over 200 miles and loved every minute of it. I have spent my entire life on bicycles.

China motors are basically a joke to me but Gawed I love them. Too pieces. lol. Each and every one of them too. I beat them all into the ground. Why for the plain ol curiosity of building one perfect one.

What has a 235 pound guy learned different from 135 pound guy ? I am not talking about some odd ball point of bullying. I am referring to engineering. Who's stuff wears out faster?

Put 100 pounds on your back go 1500 to 2000 miles lets see if the head bolts need re-torquing. If the stock motor mounts hold up. That could be a big list.

If I weighed 135 all my motors would fly stock..

Just saying.

Yes I realize regardless of what one weighs they can tell what there riding if it is faster or slower.

The China motor it self is a kit. That said have fun with it. If you are the type of guy who's curious mode it break it. Get another one like Doritos they make more. I have bushed Motors still running with over 5000 miles on them and beat on them a bunch. They have been my best motors. The porting was different too. On my stock bushed motors I had to window the piston skirt to advance the timing on them. That was how the ports were on their jugs.

If you want longevity leave it alone yes boosting the the compression puts more hurts on these motors. Especially a unbalanced motor. [crank] They run hotter too.

Look at what Foureasy did. All of the motors he is running have big time squish bands.

If indeed the heads are warping after installed? Did the folks torque them evenly? I also suspect that is a harder head to cast? Dunno I don't have a warped one yet. I don't try to mill them down to get more compression either. They are border line too much from the start. There is not really all that good of cooling on these motors either.

For the record I don't care one bit for a slant head . I like the spark plug down the middle with a sweet squish band. Not the typical cavernous one.

I run the Slant head with two gaskets. [the way it came from the factory] They have all ran fine on pump gas at 5000 foot above sea level. Yes on a hot day in July they might ping. Higher compression demands higher octane fuel. I have experimented with good result doable gasketing the jugs at the bottom lessening the compression a tad and changing the port timing.

The motors by far that seam to live the longest are the ones with the cavernous squish bands. So its a bit of a pita there. I got slant heads with 4000 miles on them. That's lucky too because the piston bearing cages inevitably seam to fly apart.

There is volumes to be said for a balanced crank!!!

The motor you compared things too Bairdco you mentioned it ran poorly from the start. I suspect port timing or spark timing dunno? Maybe the primary compression is some how different on that motor. Perhaps it is one of the jugs with smaller porting on it?

The ones that I saw run best had text book examples of an expansion chamber on them. They are in a league of there own. Without the expansion chamber [proper tuned pipe and carb] my observations I guess is use a low compression head I think it will rev out easier.

I have come across jugs looking radically different from each other. Different suppliers.

I have had jugs where I needed to window the the piston skirt and jugs where it was fine there. Jugs with beautiful clean large porting [so far the Zoom that I know of]

It is sounding more to me that the Zooms I have played with are just built for it dunno.

I keep getting Zooms I have four now personally. Between friends there's two more I know of.
Still gotta have a since of humor.

Last edited by Goat Herder; 09-28-2010 at 01:38 PM.
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Old 09-28-2010, 01:43 PM
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Default Re: Zoombicycles 80cc slant head

For longevity sake low compression head slightly under tuned motors will defiantly live longer.

Don't buy a slant head to you read up on this head the combustion chamber on this one was correctly made.
Still gotta have a since of humor.

Last edited by Goat Herder; 09-28-2010 at 08:03 PM.
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