Well I just couldn't wait to tear into the recently aquired NSR. So I just did, now I'm thinking I may be in to deep !!!! I can't believe the way these bikes are put together, quite complicated.
I've rebuilt many different engines in my day, but never a 2stroke twin, with the electronic power valves to top it off.
This thing has to have been rebuilt before... It was leaking badly between the upper and lower cases. Front cyl base gasket leaking as well. Intake boots were out of the airbox....ect......
What am I looking at here? Is this worth the time,effort,money???
Just a little freaked out at what I saw when that tank came off... feel like I'm in to deep.
What kind of damage is going to be in there on a locked up engine? Any round about costs on ALL new parts??????
_________________
MC21
04 NSR50R
93 CBR F2
98 CBR F3 track bike
95 VFR750
89 FL400R Pilot
90 FZR 4/600

The NSR engine must be one of the easyest engines ever to rebuild!

The power valves are so simple once you see how they work. Its only a servo motor with 4 cables at the end of the day.

As for the cost of motor. If its fully locked up then your looking at... round ish figures here....

Crank, £550
gaskets, £40
seals, £50
Little ends circlips, pins, dowls etc £100
pistons and rings £200
two barrel replates, £300
bits and bobs £20

That really rough rough but a full motor rebuild in parts will be about that. £1260. Thats about $2400.
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If I have to take the carbs off once more...

Would it be a good idea to get the 300 kit instead of stock? would be around the same price as to your rough prices
_________________
MC21
04 NSR50R
93 CBR F2
98 CBR F3 track bike
95 VFR750
89 FL400R Pilot
90 FZR 4/600

This thread is about to get locked!

Listen carefully.... THIS THREAD WILL NOT TURN INTO ANOTHER 250 Vs 300 DISCUSSION.

It's been done to death, and you have been warned. Go search the Forum for 300 related posts, and make your own mind up.
_________________
Andy.
NSR-WORLD.COM

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something of note is that I don't believe the 300 kit includes the crank, which seems to be the big ticket item in a ground up rebuild

if you do decide that it's too much of a project for you, PM me. I've got an empty work bench that needs a new project on it!
_________________
n00b

Andy's on it today

I wish I could get hold of that switch RC46 was on about... I'd love the power to turn the Internerd off sometimes!!
_________________
Andy.
NSR-WORLD.COM

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The reason the motor is locked up is likely a piton has seized, or the crank has failed. To rebuild it ri right your looking at $2,000 no including cylinders. A 300 kit will add $1,500+ to that figure. These are not horribly complicated motors and if you have some experiance on similar motors you should be OK. Otherwise give me a call.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

Thanks guys...

Sorry Andy, should of know that it's been gone over 1000's of times before.

Just worried that when I get it apart I may end up being half the mechanic I thought I was

Well, time to drain the fluids and see what's going on in there...

Steve
_________________
MC21
04 NSR50R
93 CBR F2
98 CBR F3 track bike
95 VFR750
89 FL400R Pilot
90 FZR 4/600

You can pull the cylinders off without removing the motor and that should tell you alot. You don't even have to pull the heads off. But, considering you don't know the history of this motor I would just do a full rebuild so you know it will be right and that you can depend on it for a while.
_________________
james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
CRF250X
748R
Porsche (many)
http://members.rennlist.com/j911brick/rennlist3_002.htm

I'm in the same boat as you, mine isn't locked but it sat for 7 years and is a non runner.

I sent Matt at Tyga an email and he sent me a parts list of just about everything needed for a major rebuild with prices.

If Matt doesn't mind I can copy and paste the parts list to you via PM and save him time.

Have a look at the Online Parts Manual. You'll be amazed at how accurate the diagrams are, and consequently how simple it is to build/rebuild a stock motor.

Torque settings are pretty much industry-wide standards based on thread size and head type (i.e. flanged and non-flanged head), and there will always be plenty of advice here to help out.

Have you read through the engine rebuild pages in the Workshop? It really isn't that difficult, and once you've done it I bet you'll soon be looking for an excuse to take it apart again!

One piece of advise I will offer though - make sure you have a good selection of tools that are fit for purpose!
_________________
Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

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Andy wrote:One piece of advise I will offer though - make sure you have a good selection of tools that are fit for purpose!

Amen. You really don't need a massive tool kit, so don't waste your money on a huge kit with a load of dubious quality kit or imprial size sockets you won't ever use. Just assemble a basic metric tool kit of the best quality you can afford. I've never rebuilt an NSR motor (yet) but I'm sure people will post up any special tools you are likely to need. Other than that it's surprising how much you can achieve with a few metric sockets, and a small collection of screwdrivers and pliers etc.

For what it's worth the best tool I've bought in the last few years was one of those little 12V cigarette lighter or battery powered electric impact wrenches designed for removing stubborn car wheel nuts. I was very dubious but I have been absolutley amazed that I have not yet encountered a clutch centre, flywheel or sprocket nut it can't shift with it's remarkable 12 volt punch - often without any need to even hold the flywheel/clutch/sprocket etc. Extraordinary! The time effort and strain it has saved me means it has paid for itself very many times over already. Brilliant bit of kit.

Get stuck in. It feels great when you fire up a motor you've rebuilt yourself.

Cheers

Wb


Last edited by wb on Wed Jul 04, 2007 12:53 pm; edited 1 time in total

I've read that rebuild how to in the workshop area quite a few times. I appreciate it being there.

I'm somewhat concerned about the special tools required to do the job properly.

I remember reading an old post about NSR-World renting those special tools out. I would guess that would be for those of you on your side of the pond right?

Thanks guys....

Yes I've read the rebuild article a few times trying bed it in the brain real deep...

Tools aren't an issue as I used to be a mechanic cars and bikes for a minute. Rebuilt lots of car engines and two stroke singles. Never have had the chance to tear into a stroker twin nor a 4 cyl sport bike motor yet...

So I got it apart. Came apart fairly easy I guess

Both jugs seem to be in good shape... Pistons as well. Neither cylinder was seized. The crank is locked. I can see one thing interesting, when I look through the reed hole I can see the the crank looks blued due to heat near the bearing closest to the clutch.

Now what????? Just a crank? Or do it all? It doesn't look like there were many miles put on it since it was apart last(not much carbon/power valves operated free).

Opinions???????

Steve
_________________
MC21
04 NSR50R
93 CBR F2
98 CBR F3 track bike
95 VFR750
89 FL400R Pilot
90 FZR 4/600