tzr/srz/rz 350-465cc

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TN-592
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tzr/srz/rz 350-465cc

#1 Post by TN-592 » Fri Jun 10, 2016 2:33 pm

Tzr belgarda frame
SRZ 660 swingarm
yzf 125 rear end
rz 350 engine

Will upgrade to a 7mil crank,at first I am planing to use stock ported cylinders and later on will buy cub or athena
Now project is on 65%Image
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Last edited by TN-592 on Mon Jan 29, 2018 8:47 pm, edited 1 time in total.

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Questo vecchio rz
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Re: tzr/srz/rz 350-443

#2 Post by Questo vecchio rz » Sat Jun 11, 2016 4:04 am

Nice start, to what looks like a good package once you have it sorted out. Keep updates as you go.
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TN-592
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Re: tzr/srz/rz 350-443

#3 Post by TN-592 » Tue Aug 30, 2016 7:18 pm

Now the I am planing to procede with my project,but I can not decide which big bore to buy.
I would be happiest with cheetath 72mil 10 mil stroker but I can not find them anywhere to buy,all I find are cub cylinders and they have stock size intake port which leads me to conclusion maybe it is not much better than athena cylinders when same size!?And then again I havent find athena cylinders which are for a 10mil stroker,and athena 392 produces 55hp which is like stock rz cylinders then why would I buy athena I could just port stock cylinders and have almost same result!?
For now highest buying procentage goes to 10mil supercub,but do they have probem at high rpm due to small intake port?
What you guys think?

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Re: tzr/srz/rz 350-443

#4 Post by ghezzi » Tue Aug 30, 2016 9:54 pm

Now I may be a silly old fart but there is something here I never understand.
I thought Athena cylinders were designed to go with the stock crank of 54mm stroke. So if you increase the stroke you fuck up all the port timing.
Ok, you can add spacer plates or pistons with different deck height, but everything is a compromise and you end up with a kludge.

Just asking, is it not better to start with a cylinder block that has been designed to run with a 58mm or 61mm crank.

CPI cylinders are designed/ported for stroker cranks - 39mm carbies - 100hp etc.
Keep in mind the longer the stroke, the higher the piston speed. You no longer have a screamer peaking at 11,500rpm, your hundred horsepower may arrive at 9,500rpm, be careful.

My 58mm stroker has rev limit set at 10K.
I'd rather ride a slow bike fast, than a fast bike slow.

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JonW
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Re: tzr/srz/rz 350-443

#5 Post by JonW » Tue Aug 30, 2016 10:12 pm

Lots of people +4 an Athena in RD/RZs and 'shees, maybe its not perfect for the timing but it does work. Cubs would be better of course, but cost more.... Id like some cheetah cubs if anyone is looking for xmas presents for me... ;)
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Re: tzr/srz/rz 350-443

#6 Post by ghezzi » Wed Aug 31, 2016 1:35 am

Admit I've never ridden +4 Athena, never seen one either but read many comments from owners on different forums 'bout narrow light switch power bands.
S'pose its all individual perceptions ...................................
I'd rather ride a slow bike fast, than a fast bike slow.

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Re: tzr/srz/rz 350-443

#7 Post by seahorse » Tue Sep 06, 2016 8:33 am

It is and your right your better to get a plus 4 cylinder port designed for a plus 4 crank for example.
I have a cub mono block plus 4 set up and it isn a light switch at all, but it must be respected particularly in the wet.
It does continue to make realistic power at 10 k much to the non believers dis belief that don't own or who have never ridden a 421, having said that the majority of power has arrived at 9 so there is no need to flog a champion horse.
On the street they are a very nice animal to ride. Bottom end is compararable to a bog stock standard 31 k with cigars and standard jetting. The magic happens from 5 and is exponential as the revs climb.
I'd liken the experience to trying crack for the first time ( addendum which I haven't ) you even have a tendency to bight down hard an your teeth when you wind throttle on and feel the hit.
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JonW
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Re: tzr/srz/rz 350-443

#8 Post by JonW » Tue Sep 06, 2016 9:14 am

[quote="seahorse"
I'd liken the experience to trying crack for the first time ( addendum which I haven't ) you even have a tendency to bight down hard an your teeth when you wind throttle on and feel the hit.[/quote]

Fave post ever!
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

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Re: tzr/srz/rz 350-443

#9 Post by evan_calgary » Tue Sep 06, 2016 12:52 pm

How did you manage the cradle and rear engine mount?

TN-592
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Re: tzr/srz/rz 350-443

#10 Post by TN-592 » Tue Nov 22, 2016 6:05 pm

Frame pictures
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Zombie
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Re: tzr/srz/rz 350-443

#11 Post by Zombie » Tue Nov 22, 2016 8:55 pm

That's one sharp looking bike! Going for the naked streetfighter look?

Cant help with the engine- I'm going straight into "Ludacris Speed" arena with mine..

TN-592
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Re: tzr/srz/rz 350-443

#12 Post by TN-592 » Thu Nov 24, 2016 8:35 pm

Thanks zombie.....yes it will be a streetfighter
Right now I am trying to sell some old parts and if I do I going to buy 521 cheetah cub

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Re: tzr/srz/rz 350-443

#13 Post by yazza54 » Mon Nov 28, 2016 8:50 am

There's no such thing as a 521 cheetah cub, do you mean super cub? 72 bore 64 stroke would net you 521.

Cheetah cubs are all 68mm bore so the biggest you can go in standard cases is 10mm crank = 465cc.

I personally would steer clear of going bigger than 68mm bore. The cubs make excellent power and respond very well to being stroked. Theres loads of huge bore super cubs etc out there not making as much power as some of us are on cubs. FYI my 443cc cheetah cub made 109 HP at the wheel...

TN-592
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Re: tzr/srz/rz 350-443

#14 Post by TN-592 » Mon Nov 28, 2016 5:29 pm

Sorry,yes I ment super cub
Your 443 made 109hp omg,what pipes and carbs do you have?

yazza54
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Re: tzr/srz/rz 350-443

#15 Post by yazza54 » Mon Nov 28, 2016 6:07 pm

TN-592 wrote:Sorry,yes I ment super cub
Your 443 made 109hp omg,what pipes and carbs do you have?
Custom made TSA pipes and 38mm flat slides

Loads of cubs out there making easily in excess of 100hp

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