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Back to the daily grind.


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Sly Fox

 
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Back to the daily grind.

Sat Jan 10, 2015 1:56 pm » Post: #1 » Download Post

In the quest for efficiency its grinding time!
Look at this naughty boost port, bit of turbulence there don't you think?



Thats better!!



Ugh, ugly flashing in the inlet...



Not now, yay!



I'm not a tuner but it is fun to tidy up the crank cases.
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Andy
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Sat Jan 10, 2015 6:31 pm » Post: #2 » Download Post

Always worth tidying the cases up when they are apart. The stock port timing is actually very good, but it's a good idea to optimise/equalise the port windows, and open up that boost port, as you noticed.

The casting flashing is ugly, and good to remove. Don't waste time knife-edging anything or polishing; there's room for a little turbulence! And don't raise the compression. A huge no-no with the NSR.
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Sly Fox

 
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Sat Jan 10, 2015 9:30 pm » Post: #3 » Download Post

Yes, just a clean and tidy up, correct the short comings of mass production.
I won't be trying anything clever, it's easy to go too far and mess it up.
Designers always have ideas to increase swirl and direction, it's best not to go round grinding lumps off willy nilly.
For example, at the end of each inlet is this weird little ramp, half has been machined off, half remains.
What does it do? Does it make a difference? I'm not feeling brave or desperate enough to risk removing it.


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Sly Fox

 
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Sun Jan 11, 2015 6:39 pm » Post: #4 » Download Post

I am surprised to see how much corrective work has been done on the production line.
This black blob looks like a bit of Devcon that has been shoved in to cover up a blow hole in the casting.


Once you get started on a tidy up it can get very addictive, especially if you are the one going to ride the bike.
Here I'm getting rid of the nasty step where the main bearing feed holes have been drilled.

Very therapeutic!
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paul g
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Sun Jan 11, 2015 7:05 pm » Post: #5 » Download Post

Good stuff! Glad to see you enthusiasm hasnt been damped down by the issues you have had with this bike.

Some time ago I asked the same question myself about those little ramps, If you put the crank in place they align with the crank flywheels and help the mixture to flow around the crank, I think Confused
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Andy
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Sun Jan 11, 2015 7:17 pm » Post: #6 » Download Post

Sly Fox wrote:
I am surprised to see how much corrective work has been done on the production line.

If it is some kind of epoxy, I doubt that was done on the production line. It is of course possible, but doubtful. That motor has almost certainly been apart before, and in a previous life, was probably even loved! Smile

I expect a former owner rectified some corrosion/erosion there.
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Sly Fox

 
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Wed Jan 28, 2015 4:01 pm » Post: #7 » Download Post

Sometimes I get carried away..
Look at this tiny piece of alloy that was left behind when the bearing feed holes were drilled.
I really want to grind it off but I don't really understand what happens to the gas flow between the right hand main bearing and the crank seal.
It does look tempting though!!!…..maybe if I remove it, oil flow to the bearing will be improved…or maybe the flow needs to be disrupted here.
This sort of thing keeps me awake at night…..I should probably put the grinder away and put the engine together!!! Razz


Have a look at were that blob of epoxy had been. I'm surprised it passéd QC, (assuming this happened in the foundry)

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Andy
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Wed Jan 28, 2015 4:24 pm » Post: #8 » Download Post

Sly Fox wrote:
Have a look at were that blob of epoxy had been. I'm surprised it passéd QC, (assuming this happened in the foundry)


That looks more like water erosion to me. I expect coolant seeped under the base gasket at some point.
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Sly Fox

 
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Wed Jan 28, 2015 4:30 pm » Post: #9 » Download Post

Good idea but we'll never know…also you'll never know how it became dislodged because I'll never tell you how I stupidly it put it in the dish washer in a moment of madness.


Doh!
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Andy
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Wed Jan 28, 2015 4:34 pm » Post: #10 » Download Post

You aren't the first to put NSR engine parts in the dishwasher!
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Sly Fox

 
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Wed Jan 28, 2015 4:41 pm » Post: #11 » Download Post

I had the 'brain wave' of using the dish washer because the cases were full of material from were I had bead blasted them.
They went in a beautiful shiny new like silver and came out black.
I cried.

A really helpful friend, (by that I mean totally unhelpful and sarcastic git) pointed out that I should not have have used a 'Finish Ultra' tablet.

This must be some sort of learning curve thing!
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Andy
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Wed Jan 28, 2015 4:58 pm » Post: #12 » Download Post

Our hack mechanic, StephenRC45, is master of dishwasher safe alloy cleansing products!

I think he's banned from the dishwasher these days, but we bead or soda blast cases professionally these days anyway. It might be nice to do a set of NSR500V cases in the dishwasher one day though, just to say we did it! Smile
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mtec666

 
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Fri Jan 30, 2015 6:11 am » Post: #13 » Download Post

"The casting flashing is ugly, and good to remove. Don't waste time knife-edging anything or polishing; there's room for a little turbulence! And don't raise the compression. A huge no-no with the NSR.[/quote]

Why is raising the compresion a huge no-no? Wouldn't it depend on what type of fuel you have access to?
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