Possible 300cc conversion

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Sheik Yerbouti
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Post by Sheik Yerbouti » Thu Nov 20, 2008 1:00 pm

Awesome, Looks pretty close.
The biggest problem I can think of is the pin hieght, as shaving 2mm off the base will most likely give the same issues as found with the KR1 when fitting the TZ pistons.
Whats the issue? I must be missing something but it seems like you can just turn 2mm off the bottom of the barrel. :?

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ScottaKR
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Post by ScottaKR » Fri Nov 21, 2008 8:09 am

Sheik Yerbouti wrote:Awesome, Looks pretty close.
The biggest problem I can think of is the pin hieght, as shaving 2mm off the base will most likely give the same issues as found with the KR1 when fitting the TZ pistons.
Whats the issue? I must be missing something but it seems like you can just turn 2mm off the bottom of the barrel. :?
The issue is weakening the area around the bolt holes which can lead to cracking. I can't remember how much they shave off the KR1 barrels for the TZ piston conversion, but I know it caused them to crack as the amount of material removed left them too weak to cope.
I think many now build up the top of the area around the bolt holes with weld (TIG I assume), and then machine the barrels but I was hopeing to avoid that. Then again, with the amount of machine work that will already have to go into this conversion (over-bore, correcting port timming, re-working combustion chamber volume and squish band) I suppose that little extra isn't a big deal. :roll:

Oh well, it gives us all something more to think about anyway. Unfortunately I won't be able to do much in the way of actually attempting this conversion for a while as I don't quite have enough cash left after buying all the bits for the naked conversion, and the top end of the current engine is still in good nic anyways (though it would be nice to have it ready in case something did go bad).
Besides, I still have to finish of the naked conversion and find that electrical gremlin so I can take it out for a blast soon.

Cheers, Scott.
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)

Sheik Yerbouti
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Post by Sheik Yerbouti » Fri Nov 21, 2008 9:34 am

Oh well, it gives us all something more to think about anyway. Unfortunately I won't be able to do much in the way of actually attempting this conversion for a while as I don't quite have enough cash left after buying all the bits for the naked conversion
Yeah I figured this for more of a long term solution as well. I still havent got mine back on the road yet, ( needs little things like fuel line and thermostat ) but the top end is pretty good.

On the other front, I've been mucking about with a gear lever, I've cut the spline and am looking at the clamp. When I get something rough together I'll send it over to ya if you like and you can try it with your aftermarket rearset.

How did you go with the electric dash/instrument cluster?

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ScottaKR
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Post by ScottaKR » Fri Nov 21, 2008 10:21 am

Sheik Yerbouti wrote:
Oh well, it gives us all something more to think about anyway. Unfortunately I won't be able to do much in the way of actually attempting this conversion for a while as I don't quite have enough cash left after buying all the bits for the naked conversion
Yeah I figured this for more of a long term solution as well. I still havent got mine back on the road yet, ( needs little things like fuel line and thermostat ) but the top end is pretty good.

On the other front, I've been mucking about with a gear lever, I've cut the spline and am looking at the clamp. When I get something rough together I'll send it over to ya if you like and you can try it with your aftermarket rearset.
That'd be fantastic! 8) I'll be more than happy to test it out for you. :D
Sheik Yerbouti wrote: How did you go with the electric dash/instrument cluster?
Been trying to work out a secure way of mounting it that isn't so obvious and easy to remove as to invite theft. Ultimately, I'd like it to look like it may have been a factory option to those unformiliar with the bike :mrgreen: . I'll be spending some quality time on it this weekend which will hopefully see it monted and wired in, but I'm still undecided whether or not to ireversibly graft it into the harness (which would be much neater and more reliable) or make an adaptor harness so it's just plug and play. I'm leaning towards permanently grafting the Acewell conectors into the harness since I'll already be re-working the layout of the loom to make it tidier with the naked conversion.
I'll post up some more pics of the naked conversion when the dash is mounted.

Cheers, Scott.
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)

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StrokerBoy
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Post by StrokerBoy » Fri Aug 14, 2009 3:36 pm

Sheik Yerbouti wrote:
Gear-lever linkage is a good idea. There's not much space round the shaft so it's tricky trying to adapt non-standard footrests to fit. A splined bracket that moves the linkage outside the frame would be very useful.
Not sure what you mean, :-k sketch what you reckon and post it up, I can get measurements off my bike and see what I can come up with. Pretty keen to see what can be done with these bikes, I'm just getting in to it. :twisted:
Just spotted a trick KR on another forum and there's a good close-up photo of the kind of bracket I'm after.

Image
Kawasaki KR250 Tandem Twin (x4) & KS-II 80,
Yamaha RD350LC,
Suzuki GSX-R750RK & RB50 Gag.

saeid
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Post by saeid » Sun May 01, 2011 7:26 am

Pls tell me did anyone increased the to 300cc or more?
How was the result?

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ScottaKR
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Post by ScottaKR » Sun May 01, 2011 1:33 pm

saeid wrote:Pls tell me did anyone increased the to 300cc or more?
How was the result?
Hi Saeid. I never got much futher than planning the basics with this (had thoughts of a longer stroke crank to add capacity and account for the shorter piston), but as usual, other things came up, including buying a house and the reno's that go with it. I've still got the bike up the back of the shed, and I do intend to finish it one of these days, but it's sadly low on the list of priorities at the moment.
I'm not sure if anyone else decided to try to follow up and complete a 300cc conversion like this, but I think it still has potential for someone with the time, patience, and of course funds to see it through.
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)

saeid
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Post by saeid » Thu May 05, 2011 4:31 pm

Thanks, I'll be sailing for a few months starting from 7th of may.
I have some spare time to think about it. The pistons available here
are 59mm, 64mm & 66mm dia.
1st one giving only 277cc and not atractive at all to do all this
modification, last one is too much to be considered! 64mm (326cc)looks
more promissing although still looking for 61 or 62 mm dia.
Take care.

miuganlee
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bb

Post by miuganlee » Fri Nov 02, 2012 11:49 am

Good..

2stroke
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Post by 2stroke » Tue Nov 27, 2012 11:55 am

We plan on using the kawasaki KE 175 piston.

We have also just finished o-ringing the top of the cylinder. No head gasket!
And more compression.

More to come.

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Top-shaggy
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Post by Top-shaggy » Tue Nov 27, 2012 12:14 pm

That sounds good 2stroke - have you got any pictures?
:D
If it takes more than 2strokes then your just playing at it..

2stroke
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Post by 2stroke » Tue Nov 27, 2012 7:56 pm

Sure do.
But wasn't able to off my phone.
Maybe I can email the picture to someone and they can up load it for me ?

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Luders
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Post by Luders » Tue Nov 27, 2012 8:47 pm

can't you just email them to yourself and host them?

2stroke
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Post by 2stroke » Tue Nov 27, 2012 9:27 pm

You have an email Luders :lol:

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Luders
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Post by Luders » Tue Nov 27, 2012 9:40 pm

I don't mind hosting a pic, but I have no emails in

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