Final KR Based Race Bike Project

Show us that box of bits in your shed!
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KR-1R
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dont call me an engineer...

Post by KR-1R »

JanBros wrote:are you gonna leave the supports for the subframe single sided ? I would put one on each side to avoid twisting forces on them :wink:
the terminology for the lugs being in single or double shear arrangement
...cross sectional force through the bolt being transferred though 1 point (with a possible detrimental bending moment) or 2 points where the bolt is supported either side (removes bending and halves the shear stress on the bolt material)

eg...
the top of the shock below is mounted single shear
where the shock attaches to swingarm is double shear
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...the majority of subframes are done single shear without problems
... because the subframe will only be carrying 1 rider (well less than 100kg static (~1000N) + footrests are carrying load too) spread across area of 4x bolts 8mm/10mm - the shear stress is ~3 MPa (<<1% = so may not be best engineering practice but is totally safe for the situation)

http://www.engineeringmotion.com/videos ... alculation
^^^ dont need to pay for an education these days

attention home platers... I WANT TO SEE SOMEONE ANODISE THEIR CARBS
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^^^ grey/black... YOSHIMURA style
Luders
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Post by Luders »

Thanks for explaining the engineering rationale behind my decision Danny =D>
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500bernie
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Post by 500bernie »

Cool vid......reliving physics lessons, all my old teachers used real life props 8)
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Post by fred »

just stumbled in ,give us a shout ben if you need any nut inserts for subframe
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Post by john-b »

wasnt that why you should do double shear? all my linkages are double shear on my ypvs to be fair just in case. Rivnut kits are pretty cheap by the way its only like a pop rivet but just leaves the nut in place in the hole if that makes any sense?
i swapped the well nuts on the reg bracket for 8 mm ones to mount my steering damper bracket more securely which may help if your running one?
I wish i knew something about KR's so i was like knowledgeable about them and everything like what you lot are ;-) :-) :-)
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Post by Luders »

Will do thanks Fred
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KFOR
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Post by KFOR »

scooble wrote:phwoarr!! :oops:
Indeed :shock:
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daz680
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Post by daz680 »

Hi Ben
just ordered this so if you need to borrow it you know where i am
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Currently building RC30 lookalike
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Post by Luders »

I'm still not 100% sure what I'm doing with the frame yet, but it's likely that I am going to want to move the fairing stay inserts, or at very least one of them, so thanks for that Daz.
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Post by Luders »

Spent most of my spare time this week cleaning off the old paint from the frame, in preparation for the anodisers.

Fairly boring, but it's still progress...

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500bernie
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Post by 500bernie »

Looking good Ben.
You will need to make sure all the fine surface marks are fully buffed out on all the visable sections and the surfaces are very flat or you will see any imperfections in the finish. I would rub these areas with 1500 then 2500 grit wet.
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KR-1R
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Post by KR-1R »

.
.
have they done welded frames before?
I was told welds might oxidise and take the colour differently.
you're going Black?
a rougher brushed finish might accept the process better and look more factory/works
brushed or mirror will be more time either way
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perhaps sand or media blast would get it even eg the levers vs hangers
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Post by Luders »

I'm having second thoughts on the anodising, but not ruling it out completely at the moment.

For now I've been working on getting it together as a rolling chassis.

The forks are away at the moment being serviced and I've added a new steering damper mount to the frame in a more advantagous position.

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I've stripped out an old petrol tank and have used it in these photos to create a cardboard mock up of the fuel cell I want made.

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I've had a screw top filler neck made up by a motorsport engineering company (rakeway), so will take that along with the cardboard mock up and fuel tap to my fabricator and get him to make the aluminium fuel cell for me.
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si.likes.guiness
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Post by si.likes.guiness »

good stuff ben 8) were looking into doing it to mine,so good to see you trying it mate.what would be the cost of having the fuel cell made? thats if you dont mind me asking
ive seen more tarts than mr kipling
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Post by Luders »

I think it depends on what sort of filler you chose, my approach isn't the most cost effective. I'll let you know the total costs when it's finished.
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