[estevns]

I've made a drawing of a K5 flywheel in case someone would like to machine their K3/K4 to spec.

As stated on the drawing a vernier caliper (0.05mm) was used to do all the measurements so good rule of thumb is to expect ±0.5mm accuracy. Crank position teeth and oil drain holes are all for illustration purpose only, I did not put them in the right position!
Let me know if any measurements should be added. I only added those which I believe to be necessary for lighten the earlier flywheel.

If someone more knowledgeable can confirm front and rear timing marks it would be great! I believe it makes sense they are positioned in relation to the feather key which are the only alignment to the crankshaft. Markings are engraved on the outer surface and will be lost in the process.

 

[Missing Link]

OH.....MY....GOD......!!!

You sir, are a legend...... now, i just need a lathe.....well a better one than the one at my work..... HA HA

Excellence in the extreme.....

I will make this sticky for others

 

[estevns]

OH.....MY....GOD......!!!

You sir, are a legend...... now, i just need a lathe.....well a better one than the one at my work..... HA HA

Excellence in the extreme.....

I will make this sticky for others

You welcome - planning to lighten it sometime in the near future?
When I do the swap I'll inspect the old flywheel and see if I can foresee any pitfall. It's always so simple to make parts and assemblies in the CAD software – soon after you meet reality.

Looking at the posts made by Jumjum a few months back i shouldn't be too much hassle. Schmidt also mentions feather key and front timing mark to be aligned.

Flywheel timing marks

In the process of re-glueing the magnets to my K3 flywheel I went one step further and removed 1,1kg of material in a lathe to ligthen like the K5 flywheel. Unfortunately i forgot to take note of the timing marks and now they are gone. Can anyone help me? Mabye there is some reference point I...

www.sv-portal.com

 

[Missing Link]

Yeah, my only thought would be the material thickness on the "bottom" corner, where the 45 degree shamfer is......one would assume that keeping that
transition fairly even would gaurd against stress fractures

 

[estevns]

Yeah, my only thought would be the material thickness on the "bottom" corner, where the 45 degree shamfer is......one would assume that keeping that
transition fairly even would gaurd against stress fractures

I'll measure again to see if I made a mistake and have a look at the heavy flywheel once it out. Shouldn’t be too long.

That said, to me it doesn’t look that bad. But my experience as mechanical engineer is almost non existing when it comes to engine components, so chances are I’m completely wrong. Bigger and more slowly moving structures and machinery are more my thing - agriculture equipment and wind turbines.

 

[Missing Link]

Compared to most superbike 4 bangers, SV's are bigger slow moving tractors.....

Engineering is the same all round....principals are no different.....i dont think so anyway.....

 

[Urbanjugle]

exactly SV's are the slow moving tractors compare inline 4s
anyway good job drawing the flywheel...
CAD must make it easier...i remember when i was in tech school we had to do drawings on special kind of transparent paper with ink ...

 

[Missing Link]

...i remember when i was in tech school we had to do drawings on special kind of transparent paper with ink ...

I still have my hammer and chisel for when i did drawings like this.....

 

[Mike C Riding Lessons]

I've made a drawing of a K5 flywheel in case someone would like to machine their K3/K4 to spec.

As stated on the drawing a vernier caliper (0.05mm) was used to do all the measurements so good rule of thumb is to expect ±0.5mm accuracy. Crank position teeth and oil drain holes are all for illustration purpose only, I did not put them in the right position!
Let me know if any measurements should be added. I only added those which I believe to be necessary for lighten the earlier flywheel.

If someone more knowledgeable can confirm front and rear timing marks it would be great! I believe it makes sense they are positioned in relation to the feather key which are the only alignment to the crankshaft. Markings are engraved on the outer surface and will be lost in the process.

View attachment 117720

I'm considering buying a K5 flywheel for my 2003. Did you go right to the JB Weld on it to prevent the magnets from failing?

-Mike C.

 

[Missing Link]

I'm considering buying a K5 flywheel for my 2003. Did you go right to the JB Weld on it to prevent the magnets from failing?

-Mike C.

Absolutely.....dont pass go, dont collect $50 ....go straight to the JB Weld ......

 

[estevns]

I finally got around to do the swap yesterday, just took some pictures side by side to give some idea of how much needs to be machined off.
That K3/K4 flywheel is one chunky boy.

 

[Missing Link]

Its ridiculous that it was that big in the first place....

Tossing up whether to machine it myself on my work lathe....smallish and it will ba 30 mins at a time sort of thing....
Or give it to someone.....but the cost of that might approach a new K5 one anyway......

 

[estevns]

You got some real struggles down under - sunny and warm weather all year around 😁 Guess you dont have any downtime. It would be nice to be able to ride all year, but the cold and wet winter gives opportunities to take on longer projects without missing out.

If it wouldnt be so damn expensive to ship from EU to AU you could get my flywheel for cheap and machine that one. I could easily sell magnets to someone else in need.

 

[Missing Link]

I have a spare 03 flywheel......i just gotta decide what to do....so many other things demand attention in a dollar/pound/kroner/franc/lire sense.....