I finished stripping down my engine last night to find the right hand main bearing had given up the ghost and wondered if this was a common problem or if it was caused by lack of use and oil draining away from that bearing.
I have put a picture up of heat marks on the crank from this side of the bearing and wondered if this is from the overheating bearing or maybe from something else like a crank rebuild?

I asked a very knowledgeable friend of mine about this. He said:
The heat marks are caused by the heat treatment process used by Honda.
They induction harden the pin bore, and the integral pin area.
This is in effect "spot treatment" that heats and thus hardens only those areas that need it, the rest of the forging is left ductile to increase fatigue strength.
Its very normal on an NSR flywheel.

You may well be able to get away with just replacing that bearing.
It is starting to look as though the failure of that bearing is indeed reasonably common. See this thread.

<Rant>
As an aside: after being on this forum for approx 18 months I am starting to understand how things work here.
If you look at the list of services provided by NSR-World at the bottom of the performance page you will see that they provide a crankshaft rebuild assessment fee of £25, so I doubt that many of the "senior" members here will offer up any advice.

I guess the moderators put a lot of time into this site and it is possibly fair enough to shut down topics like this with a post that says "This is what our £25 assessment fee is for"?
Perhaps it is 'not really allowed', to give advice on this matter in this forum, as it potentially eats into the moderators cash supply?
But HEY!,... this is a forum
Sometimes I feel as though if this forum was a TV channel, it would pay per view. That is fine, as long as it is stated up front.

I fear that this is probably another example of some of the "mysterious" rules that exist in this forum, but are not mentioned in the "sticky's". Hopefully not.
I just wish that issues like this were made very obvious and transparent by stating them in the sticky's for all to see. Especially for the new members.
This has the potential to be an excellent forum, and I think that not having things like this mentioned up front in the sticky's really doesn't help this forum.
</Rant>
Sorry for the rant, but just trying to help,.. actually.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...


Last edited by TuckerBag on Wed Nov 23, 2011 7:27 pm; edited 1 time in total

The assessment fee works like this.

You send the crank to NSR-World. It is then fully stripped, clean and inspected. If it deemed to be serviceable (many aren't) it is rebuilt. If it's found to be damaged in a way that can not be repaired (such as pitting to the big end pins, an integral part of the crank web) then you pay £25.00 and they send you your crank back.

If however the crank is in serviceable condition and can be rebuilt the assessment fee is included in the price of the rebuild.

The heat treatment of the cranks depends on the model and age of the cranks as different processes have been used though out the NSR engine life.
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If I have to take the carbs off once more...

When you've had 10~15 years of people trying to bleed you for information, despite giving pretty much everything you can to them already, and having so much of it on the Main Site and within the forum archives anyway, answers to obvious questions tend to get short.

Sometimes it may be a bit unfair on the person asking, as they're not necessarily aware the info exists. However, there are plenty of people here who can answer (having been on the forum for many years, and seeing countless recurring topics!), but generally it's expected that only a handful of us should! When we don't we come under fire for not sharing, despite just about everything being answered at least once already, and more often than not being freely available on the Main Site.

In my personal opinion, this is probably one of the most comprehensive one-make sites on the net, and there's probably more free, accurate, and technical information here than anywhere else in the world. It's also kept in as plain English as possible, so non-English speakers have a chance to participate and understand it, but even that's called into question by those with nothing better to do than criticise.

Get over it.


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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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TuckerBag wrote:
so I doubt that many of the "senior" members here will offer up any advice.

I don't know if I count as a senior member but obviously the outer mains are easily pulled off or pressed on.

Whether it's wise to just replace one dead bearing is up to the individual, I'm of the "if it's not broke don't fix it" and "don't spend £200+ when you can spend £35" mentality but that's just me.
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

I pay`d last night to become a titanium member. how long does it take to let me access all areas? thanks

twinpop wrote:
I pay`d last night to become a titanium member. how long does it take to let me access all areas? thanks

No idea why you weren't updated automatically. PayPal doesn't seem to update the database at the moment.
_________________
Andy.
NSR-WORLD.COM

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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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andyo wrote:
I finished stripping down my engine last night to find the right hand main bearing had given up the ghost and wondered if this was a common problem or if it was caused by lack of use and oil draining away from that bearing.

Bear in mind that most cranks haven't been rebuilt yet, and that all original cranks are at least 15 years old, and some 24 years old!

Your average MC21 crank had been in service for 20 years now... a worn out right hand main can hardly be classed as a "common" problem, although that bearing is undoubtedly under the most duress.
_________________
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, I agree with you and am sympathetic to your cause. You have done an EXCELLENT job with this site. No question about it at all!
And it is perfectly reasonable (and expected) that your patience may wear a bit thin after years of NSR related altruism

Sorry if my comments come across as being a criticism. I don't mean to cause any grief. I am trying to help.
I'm just trying to suggest a way of improving things a bit.

Sometimes when you are immersed in a situation for an extended duration, you can have trouble seeing the forest for the trees.
I myself have been in such a situation a few times and have found that a fresh perspective can be quite helpful?

I am only seeking clarity for new members and in turn suspect this will reduce frustration for senior members.

Tuckerbag out, and over it.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...

Andy wrote:

twinpop wrote:
I pay`d last night to become a titanium member. how long does it take to let me access all areas? thanks

No idea why you weren't updated automatically. PayPal doesn't seem to update the database at the moment.

Thank you I have access now.

Part of the problem for the Forum and (more to the point) any associated service is it has to do the job properly. Presumably it's been decided that to visually check a crank and if an outer main is all that's obviously worn just replace that isn't good enough to put the name to.
Besides the bearings are available in the Marketplace and even if you can't do it yourself any old engine builder/race workshop/motocross dealer will be able to point you in the right direction. No one sane would ship a crank across the country for such a small job.

It's all very well me telling someone that just replacing the one wizzy bearing will fix the problem and in the short term I'm sure it will. If you're not shy with the tools a good few hours, a gasket kit, the offending bearing and (if you fancy it) a couple of new crank seals will see the bike working again. But I know Andy and Steve well enough to know they wouldn't run such a crank in their own bike and won't be offering any such "service".
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

Andy wrote:However, there are plenty of people here who can answer (having been on the forum for many years, and seeing countless recurring topics!), but generally it's expected that only a handful of us should!

I will just say one last thing while I'm on this crusade, again, please try to think of it as trying to help rather than criticising:
I think that the senior members may have possibly unknowingly created an environment in the forum where less senior members are put off replying to topics with actual real useful information, for fear of stepping on the (potentially financial) toes of the senior members.

Certainly, when I replied to Andyo with info about his crankshaft (above), I felt that the moderators may "tell me off" for encroaching on their realm of the £25 inspection fee.
So I took the bull by the horns, and climbed to the morally high ground.

If I lived in the UK, and regularly met the senior members at track days, I would not be so bold as I am here. (I live in NZ and can hide amongst the sheep)
I most certainly would not want to get offside with such a potentially useful group of people. So I would say nothing and just "get along".
Sadly, I suspect that this is the case for many NSR fans in the UK.

This site could be an excellent one if this type of environment was just "cast out" and everyone would, in turn, get more out of their NSR's.
At the end of the day we are all bikers and we are all addicted to NSR's and the smell of Castrol TTS!

Please don't take offense Andy. I sincerely am just trying to help. Really.
You can always say that "if people don't like it, they can go somewhere else". Just like the the big supermarket chains, huh?
With monopoly, comes the responsibility of fairness; in a morally correct world anyway.

Final comment: I take my hat off to you Andy for doing an EXCELLENT job here. Please keep it up, and continually seek out ways to improve this forum.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...

TuckerBag wrote:Certainly, when I replied to Andyo with info about his crankshaft (above), I felt that the moderators may "tell me off" for encroaching on their realm of the £25 inspection fee.
So I took the bull by the horns, and climbed to the morally high ground.

If I lived in the UK, and regularly met the senior members at track days, I would not be so bold as I am here. (I live in NZ and can hide amongst the sheep)
I most certainly would not want to get offside with such a potentially useful group of people. So I would say nothing and just "get along".
Sadly, I suspect that this is the case for many NSR fans in the UK.

Then you (and they) are mistaken, although (and I do agree with you) some here are guilty of guarding their "intellectual property" maybe a little too closely there's not much to be concerned about, they may bark a bit but they have no bite.
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Please do not PM me technical questions, if you can't find it on the Forum start a thread

TuckerBag wrote:
for fear of stepping on the (potentially financial) toes of the senior members.

I don't think you could have made a more inaccurate assumption!

In case you are wondering, I have no involvement in the running of this forum whatsoever.
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Rich
MC21 Track Bike / RS250 NF5 'Spencer', NX5 'Cadalora' & NXA 'Aoyama' / RS500 / Two Brothers Racing RC30

Thank you Rich.

While I don't see why I should have to defend my position on my own website, created for the benefit of others, and consequently should in my opinion therefore be accepted for what it is by those who choose to use it and its resources, I will say that the financial gain from it is extremely small.

I've given away memberships to long standing members, I've made losses in the Marketplace after making mistakes calculating prices and exchange rates or shipping (2 members just recently can attest to this), and even track days that were in profit saw that profit spend on drinks for everyone after the event. Do you see masses of advertising on the site? There are items in the Marketplace (such as the crank bearings) that are there for the benefit of other members, and ship direct from them... I make nothing! I have even lost money on PayPal transfers to Charles to cover manual sales! So don't assume my moderation of this forum is financially motivated.

By all rights I should be making a killing from this site, but I don't.

I have nothing more to say on this matter.
_________________
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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