NSR250R Wiki created

Today I created an NSR250R wiki using Google "Sites".

https://sites.google.com/site/nsr250rwiki/

Maybe it will grow into something quite useful, maybe not.
Feel free to contribute.

Over time I hope to add most of what I have learnt about the NSR250 to this wiki for future reference.
And hopefully it will be useful to others as well.

NSR250 wiki
NSR wiki
Honda NSR wiki

<Edit 15/08/2021> Google sites are updating on 1st September 2021.
The new updated NSR250wiki is HERE.
The old classic site will still remain, but everyone should shift to the new site.

 </Edit>

Rear Suspension Link Plates. Part 2

Today I received 2 pairs of rear suspension link plates in the post.
I had them cut out of 6mm thick 6061-T6 aluminium by Fabrum Solutions in Christchurch, NZ.
The 4 plates cost NZ$160 ($40 each). The cut quality is pretty good but not quite perpendicular to the plate. It will be OK.

I used the files that I made available in this post.
I will play about with fitting them soon just for a bit of a play around.

One pair is just a copy of the HRC drawing on NSR-World.
The other is half way between the HRC plates and the stock MC18 plates.

Also, I am going to drop to 125 main jets (from std 128) and drill 4 holes in the air box and do some plug chops to see whats going on.

I took the bike on a ride with a friend (on a KTM690) last weekend but when I hit reserve tank the bike started to play up as though the jets were getting blocked or summit?
So I have pulled the tank off and checked things out, and pulled the carbs off.
There was a bit of "stuff" in the float bowls.
I have put an inline filter in the fuel hose as a result.

NSR250 TT-F3 cases

A friend put me onto a Yahoo! Japan auction that had pictures of a set of  F3 cases:

Quite nice pictures I thought.
The mods above are fairly similar to what I did.
I did not bother to fill in around the oil feed pooling areas
But these cases do not have material added on the left hand wall of the left hand reed block intake area.

Summer is coming. And thanks for the thanks.

Dyno testing at some stage
Well, not much has been happening with the NSR over Winter.
I was planning to do some dyno runs over winter, but I am yet to get around to doing that.

Ideally, I would like to have an Ignitech ignition all set up before going to the dyno so I can make good use of the time. Also, I would like to organise two or three other NSR's to be at the dyno at the same time to reduce costs and increase fun.
For bore and piston safety, a pair of EGT sensors would be a "Nice to have".
(EGT = Exhaust Gas Temperature. Anything over approx. 1250 degrees [at a distance of approx 80mm from piston] is pushing your luck apparently)

Thanks for the thanks.
Initially this blog was started up just to keep a dairy of my progress. At the time, blogging was kinda new and cool, so I was keen to try my hand. However, it has developed into something a little bit more than that. Clearly there are a few people out there that have found it to be a useful online resource for their own restoration projects.

I would like to thank all the people who have sent me messages of encouragement over the past years regarding this blog.
It can be a bit of a hassle stopping right in the middle of NSR work to take photos and note down details. And then sitting down afterwards at the computer and trying to explain the actions of the day does take a bit of self discipline sometimes.
It really does help when people acknowledge your efforts. It helps to make it all seem worthwhile.

I will (anonymously) list a couple of these comments below:
1) TuckerBag, I have actually read your whole blog, kind of the inspiration behind me pulling my one out of storage.

2) I have visited your blog many many times during the restoration of my MC18-II. Searching the net in those days, your blog was the most helpful, with pics and nice writing. And bear in mind that I was visiting your blog every time I needed something. Thank you again and again TuckerBag.

It pleases me that this blog is inspirational and useful for some.

And to those that take the time to let me know,.. you're welcome. :-)

http://www.twostrokeracelab.com/

http://www.2strokers.com/index.php?topic=184.0

Some blog statistics

Back in 2008 when I started this blog it got about 200 visits per month.
This has slowly climbed and since about October 2011 it has been approx 1200 visits per month.
The best month was February 2012 with 1800 visits that month.

I "monetised" the blog; this placed adverts within it, and as a result I have so far made about USD$13.00
Google doesn't pay out until you get to USD$100.

Blogger Stats Page over all time

Wet Weight of 155kg. Speedo accuracy. 32,000kms

I took a set of scales up to Dave's today to do a full wet weight comparison between his MC18 R5k and my MC18 R6k.

First of all let me define "Full Wet Weight" for a road legal MC18:
1) Full radiator
2) Radiator overflow tank full up to the "Upper" mark
3) Gearbox oil full up to the dipstick
4) Correct amount of oil in the front shocks
5) Full two stroke oil tank
6) Full petrol tank when on the side stand
7) Full brake fluids (negligible)
8) New-ish tyres
9) No tool box under the pillion seat
10) All road legal gear: Rego plate etc. All lights. Horn. Rear view mirrors, and pillion pegs.
11) At least 3mm of wear left on all brake pads
12) All brake discs within wear limits
13) Standard battery. Not a lightweight Lithium-Iron-Phosphate or similar.
14) Kick start and side stand on bike.

Full Wet Weigh-in. R5k vs R6k

Dave's R5k is pretty much bog standard except he has MC21 crankcases and crankshaft which are probably very similar in weight to MC18 R5k.
My R6k has:
Supposedly lighter Chinese ABS fairings
Lighter mufflers that I measured to be 1.5kg lighter than my standard mufflers
Lighter MagTek rims front and rear
Dry clutch
SP front and rear suspension.

It must be noted that despite having a dry clutch and MagTek rims, the SP has more complex front fork internals and a remote reservoir on the rear shock.
The overall result is that a standard R6k is approx 1kg heavier than an R5k according to Honda.

Front Rear Total (R5k from manufacturer)
73kg 76kg 149kg
Front Rear Total  (R6k from manufacturer)
74kg 76kg 150kg

For Dave's R5k we measured:
Front    Rear      Total
79.5kg  77.9kg  157.4kg (8.4kg heavier than Honda's spec)

For my R6k we measured:
Front    Rear      Total
78.9kg 75.9kg 154.8kg (4.8kg heavier than Honda's spec)

That makes my R6k 2.6kg lighter than Dave's R5k.

So, lets add 1.5kg to my R6k weight to allow for standard mufflers.
Then in order for my R6k to be the standard 1kg heavier than Dave's R5k, this would imply that my fairings must be approx 2.1kg lighter than the standard fairings. This sounds about right to me.

The error in the two sets of bathroom scales that we used is probably less than +/- 1kg each.

I would still like to know:
.The actual, real, measured weight difference between my Chinese ABS fairings and standard fairings
.The actual real, measured weight difference between standard wheels and MagTek wheels.


How accurate is the NSR250 speedo?
Well, I find that in 5th gear at 10,000rpm the speedo indicates exactly 150 km/h
Now, with a rear tyre circumference of 2010mm, and standard 15/42 drive sprockets, your actual speed calculates out to be 146 km/h.
So I think that the NSR250 MC18 R5k/R6k speedo is approx 3% optimistic on standard gearing.
190km/h indicated is really about 184km/h

Today I clocked up 32,000kms on the speedo.

Quick Fang

This morning was a nice crisp fine Autumn morning so I thought I'd take the scoot for a quick fang.
I went out in to the shed and adjusted the rear brake lever position, the gear change lever position and lubed up the chain.

I went for a gentle spin up to Dave's. He was not home, but I took the front spark plug out just to see how it would read. The bike is currently on std jetting.

Not a good focus on the insulator but you get the idea.

I also took a few pictures of the bike while I was up at Dave's.

On the way back home from Dave's I gave it a good blast. Now of course, I would never speed on public roads. However, I would imagine just from the general vibe of the bike, that it probably pulls quite well up to about 190 km/h indicated with 16/42 sprockets. And I imagine that it would sound pretty sharp and crisp and have quite a nice bark to it with the free flowing mufflers as well; even though just on standard jetting.

The bike seems to run a bit better every time I ride it. It has only done about 70km in total since I got it going, so maybe the rings are "bedding in" or something.

I only rev'd it out to approx 11,700 rpm max, but it will definitely rev out past that.

I took the plug out when I got home, which is only about 1 minute from the motorway. Not quite a plug chop.

Plug colour after a fast ride.

For road use, I am pretty happy with the color of the plug. I guess it's about time to think about drilling a couple of 20mm holes in the top of the air box.

Overall I am extremely happy with the bike after a quick fang today. I still need to tweak the suspension a little and make other small adjustments, but overall there was a smile on my face today.

Oh, actually there was one thing that I was not super happy with: the handlebars set off into shaking about very easily if I took my hands off the bars.