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How much is too much to take off a flywheel?


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fontyyy

 
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How much is too much to take off a flywheel?

Tue Jul 19, 2011 7:05 pm » Post: #1 » Download Post


This much Shocked
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Alzazorq
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Tue Jul 19, 2011 7:22 pm » Post: #2 » Download Post

Looks fine, can measure mine if you want to know...

Remember to get it balanced again!
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fontyyy

 
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Tue Jul 19, 2011 7:56 pm » Post: #3 » Download Post

It was a retorical question...that line about 1mm from the edge is a massive crack round it!

It's that bad you can feel the vibes and the bike misfires as it shakes up and down.
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anonymous.shyster
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Tue Jul 19, 2011 9:29 pm » Post: #4 » Download Post

So, the crack happened on the bike after it was lightened? Or did it appear whilst machining?
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Harryredchow

 
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Tue Jul 19, 2011 9:47 pm » Post: #5 » Download Post

I think that may have been too much Wink
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fontyyy

 
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Wed Jul 20, 2011 12:39 am » Post: #6 » Download Post

anonymous.shyster wrote:So, the crack happened on the bike after it was lightened? Or did it appear whilst machining?


On the bike, it's probably done about 300 miles on track.

There's another crack round the inside too;

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anonymous.shyster
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Wed Jul 20, 2011 12:47 am » Post: #7 » Download Post

So exactly how much was taken of, in quantitative terms?
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Alzazorq
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Wed Jul 20, 2011 6:53 am » Post: #8 » Download Post

LOL, ye too much then...

Didn't see the crack there, BTW did you balance it again before doing the 300miles ?

When we did mine we took an old flywheel and cut it open, we then measured how thick the steel was(cant remember) and then worked out how much we could take off safely.

There isn't much steel there in the first place, most off the weight is the magnets.

Mine now measures 108mm, originally it was 110mm so its 2mm off for those who's maths aren't too great. Smile

After that I got it balanced again and it did a full years racing with no problems and no cracks.
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fontyyy

 
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Thu Jul 21, 2011 11:51 am » Post: #9 » Download Post

It's had 1mm taken off which is about 1/2 the outer shell and a tiny amount taken off the face. A couple of NSR owners have commented it's had a lot taken off.
No idea about balancing as I bought it like that, there is a little bit removed which implies it's been done but that could be from before it was lightened.

The weight loss is only about 200 grams (the stock flywheel weighs about 1.1kg), as you say if you remove the inner shell and the magnet you lose far more (but also lose the charge circuit).
All weights from digital bathroom scales with just 1 decimal place measurments so not perfect.

Anyone know what the Tyga HRC copy flywheel plate thing weighs?
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Alzazorq
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Fri Jul 22, 2011 11:32 am » Post: #10 » Download Post

No idea about balancing as I bought it like that, there is a little bit removed which implies it's been done but that could be from before it was lightened.


Yes the counter sink holes will be from Honda. You definitely need to balance it again after the skimming or it WILL crack.

Anyone know what the Tyga HRC copy flywheel plate thing weighs?


No sure, can weigh it for you in the coming week if you need. I recon its about 1/3 of the skimmed unit. I will also weigh my skimmed unit to compare.
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fontyyy

 
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Fri Jul 22, 2011 2:26 pm » Post: #11 » Download Post

If it's that sort of difference that's fine.

What I'll probably do is at the next trackday I'll run the one without magnets with a good fully charged battery (the battery currently on the bike isn't good) and if it's OK for a couple of sessions at a time I'll get one from Tyga next time I order some bits.

Unless someone has one going spare, if so PM me, and don't put a "PM sent" reply in this thread...WTF is that about?
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2Smoke

 
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Tue Jul 26, 2011 8:21 pm » Post: #12 » Download Post

fontyyy wrote:If it's that sort of difference that's fine.

What I'll probably do is at the next trackday I'll run the one without magnets with a good fully charged battery (the battery currently on the bike isn't good) and if it's OK for a couple of sessions at a time I'll get one from Tyga next time I order some bits.

Unless someone has one going spare, if so PM me, and don't put a "PM sent" reply in this thread...WTF is that about?


Fontyyy,

I run my old shonker with the magnets removed.. With a new, fully spunked up battery it lasts a couple of sessions quite happily. I kept meaning to hook a dvm up to keep tabs on the battery voltage as I was going round..

They really don't like a low battery though, as I'm sure you know!
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fontyyy

 
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Tue Jul 26, 2011 8:44 pm » Post: #13 » Download Post

Indeed they don't, and I have reliable info the Tyga total loss flywheel is 350 grams.
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2Smoke

 
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Tue Jul 26, 2011 9:00 pm » Post: #14 » Download Post

That's quite light.. Be interesting to do a 'back to back' test on a dyno to compare Vs stock..
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anonymous.shyster
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Wed Jul 27, 2011 5:30 am » Post: #15 » Download Post

How much, and where do TYGA remove material?
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Last edited by anonymous.shyster on Wed Jul 27, 2011 6:48 am; edited 1 time in total
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