Gen 2 busa hot start issue.

[Hayabusa Wannabe]

"So the mechanic called and says that the crank needs to be changed. He says the bearings are sticking to each other."

Was the engine working fine when you took it in and only switching gears was a problem? If yes, then why would there be a serious engine issue now?

This sounds completely made up. One could do this kind of damage if they never changed the oil in 35000 miles and also you would have noticed severe running problems as soon as you began riding this bike. These engines are extremely reliable.

What is the bill for the transmission fix? I would pay it, take the bike, and run fast and far from these people. If only the hot start is a problem, the response to that is, "Welcome to Hayabusa ownership."

 

[Ryan Utah]

It sounds like as if the battery is dead. But it’s not.
Only happens when the bike is hot.

The mechanic opened the engine and told me that the crank bearings are worn out and are sticking to the crank when hot.
Could this be the issue?

 

[Ryan Utah]

Yes th

"So the mechanic called and says that the crank needs to be changed. He says the bearings are sticking to each other."

Was the engine working fine when you took it in and only switching gears was a problem? If yes, then why would there be a serious engine issue now?

This sounds completely made up. One could do this kind of damage if they never changed the oil in 35000 miles and also you would have noticed severe running problems as soon as you began riding this bike. These engines are extremely reliable.

What is the bill for the transmission fix? I would pay it, take the bike, and run fast and far from these people. If only the hot start is a problem, the response to that is, "Welcome to Hayabusa ownership."

Yes the engine had no problems at all

 

[sixpack577]

The mechanic opened the engine and told me that the crank bearings are worn out and are sticking to the crank when hot.
Could this be the issue?
View attachment 1668484

View attachment 1668485

View attachment 1668486

Looks like normal wear to me.
Do they look worn enough to change?
Sure...but did he measure the crank journal? I bet not, and because there is nothing wrong with it.
Would a bad bearing make noise?
Yes...but not only would it and the crank be in much worse shape...but the bearing would have to spin...and those bearings have Not.
How can you tell? Just look at them, you can clearly see the bottom half of the bearings seated flush in the case...and they are Not going to spin and end up 100% in the correct spot again.

 

[Bumblebee]

Yes th

Yes the engine had no problems at all

That engine would have to be either seriously abused or starved from oil to do damage to those bearings...

They don't look fried to me...too bad he already has the engine apart and you are now on the hook for that expense.

Take a look at all the Hayabusa owners who have high miles on their bikes and have never had the engine apart even though some of them visit the drag strip or run in the high rpms occasionally...

At 32,000kms your engine is just getting broke in.....

 

[Ryan Utah]

Looks like normal wear to me.
Do they look worn enough to change?
Sure...but did he measure the crank journal? I bet not, and because there is nothing wrong with it.
Would a bad bearing make noise?
Yes...but not only would it and the crank be in much worse shape...but the bearing would have to spin...and those bearings have Not.
How can you tell? Just look at them, you can clearly see the bottom half of the bearings seated flush in the case...and they are Not going to spin and end up 100% in the correct spot again.

Suggest me on what my next step should be.
Should I just change the bearings?
Or what else

 

[Ryan Utah]

Should

That engine would have to be either seriously abused or starved from oil to do damage to those bearings...

They don't look fried to me...too bad he already has the engine apart and you are now on the hook for that expense.

Take a look at all the Hayabusa owners who have high miles on their bikes and have never had the engine apart even though some of them visit the drag strip or run in the high rpms occasionally...

At 32,000kms your engine is just getting broke in.....

I just get bike back and look for other resolves?
The mechanic says he has checked every other possibility , however I wouldn’t trust them.

 

[sixpack577]

Suggest me on what my next step should be.
Should I just change the bearings?
Or what else

What was the original issue?
2nd gear slipping?
With no engine issues?
Correct?
and what is the year and mileage?
Sorry, but it's 3 pages and I can't keep up with all the threads.

 

[Ryan Utah]

I am certain that the engine is not the source of the issue.

That engine would have to be either seriously abused or starved from oil to do damage to those bearings...

They don't look fried to me...too bad he already has the engine apart and you are now on the hook for that expense.

Take a look at all the Hayabusa owners who have high miles on their bikes and have never had the engine apart even though some of them visit the drag strip or run in the high rpms occasionally...

At 32,000kms your engine is just getting broke in....

 

[Ryan Utah]

What was the original issue?
2nd gear slipping?
With no engine issues?
Correct?
and what is the year and mileage?
Sorry, but it's 3 pages and I can't keep up with all the threads.

The issue was that I was riding hard and the gear got stuck in 5th and would only go up to sixth and come down to 5th wouldn’t go below that.
No prior problems at all whatsoever with anything.

 

[Ryan Utah]

Looks like normal wear to me.
Do they look worn enough to change?
Sure...but did he measure the crank journal? I bet not, and because there is nothing wrong with it.
Would a bad bearing make noise?
Yes...but not only would it and the crank be in much worse shape...but the bearing would have to spin...and those bearings have Not.
How can you tell? Just look at them, you can clearly see the bottom half of the bearings seated flush in the case...and they are Not going to spin and end up 100% in the correct spot again.

I am uploading a video
Please give it a watch Youl understand the issue better.

 

[sixpack577]

I am uploading a video
Please give it a watch Youl understand the issue better.

ok, will do

 

[Bumblebee]

Should

I just get bike back and look for other resolves?
The mechanic says he has checked every other possibility , however I wouldn’t trust them.

Once its all back together that is......

I agree with you that the engine is not the source of your issues...if it locked up in 5th, the transmission would be the issue.....

And as for the hard start issue, I've provided a few links to threads on this.....I'm too lazy to go into the owner's manual to provide an excerpt of the hard start procedure but its there....

 

[Ryan Utah]

Hi please watch this video
I’ve made to be more informative about the issue I’m facing

"So the mechanic called and says that the crank needs to be changed. He says the bearings are sticking to each other."

Was the engine working fine when you took it in and only switching gears was a problem? If yes, then why would there be a serious engine issue now?

This sounds completely made up. One could do this kind of damage if they never changed the oil in 35000 miles and also you would have noticed severe running problems as soon as you began riding this bike. These engines are extremely reliable.

What is the bill for the transmission fix? I would pay it, take the bike, and run fast and far from these people. If only the hot start is a problem, the response to that is, "Welcome to Hayabusa ownership."

 

[Bumblebee]

I'm going to say that diagnosing this over the internet is next to impossible.....hands on is the best approach but in this case it's impossible.

As a rundown of what we know:

-bike has 32,000 kms on it
-it developed an issue with 5th gear of which the mechanic said some parts were broken (what parts-shifter fork?)
-transmission was fixed, and bike started and ran?
-bike developed a hard start issue where the battery appeared dead-wouldn't crank engine
-battery was changed to no avail
-starter clutch was changed to no avail
-bike still wouldn't start
-dealership tells you the crank bearings are worn out along with the crankshaft journals which is causing the engine to bind......dealership also tells you 32,000kms are a lot and are pushing you towards a gen 3......go figure.....

Pictures provided of the crank and bearings don't look worn out.

I take it the oil change intervals were followed and no shavings were found in the oil....I also take it there was no loud noises coming out of the engine?

Did the bike overheat.....really overheat to the point it shut down?

What does the clutch pack look like?

 

[sixpack577]

Hi please watch this video
I’ve made to be more informative about the issue I’m facing

First of all, that Was a very good explanation, and helps alot.
Ok, you have the Hayabusa hot start issue...and that is All.
There is Nothing mechanically wrong with the engine.
Those crank bearings in the picture, are as said, they are ok. They clearly have Not spun, which they have to do if they had 'stuck' or seized to the crankshaft.
Furthermore, assuming the bearings had stuck to the crank, the crank would still Not need replaced.
The crank journals would need machined/milled smooth again to the next size, and oversize bearings would be used, as this is standard procedure, and much cheaper.
So again, there is nothing wrong with the engine.
As for the fan into the coolant resivoir, it sounds exactly as you said, the previous mechanic left bolts loose.
As far as just changing crank bearings, there is no harm in that, but more so...there is no need to.
I would tell them to put it back together and 'fix' nothing else.
As for the transmission; did they ever say exactly what was wrong, or show you old/bad parts?
And, the hot-start issue only showing up after the transmission work may still be a coensidence.
Unfortunately, there is no 100% known cause of the hot-start on the Busa, and it is hard to find since it does not always happen.
The only part that I would personally change would be the regulator/rectifier.
They do commonly go bad, and they can cause strange electrical problems.
There was also a couple of recalls on them on earlier model gen2's.
Will this fix the problem? Most likely not, but at this point, through process of elimination, that is one part that does not hurt to replace, as there is no way to accurately test them.
And if you are unfamiliar with the regulator/rectifier, it is the cast aluminum gray box with cooling fins and one plug going into it, and is mounted under the rear shock and swingarm.
Otherwise, get your bike home, and stay tuned, we'll help you figure out the rest.

 

[Ryan Utah]

I'm going to say that diagnosing this over the internet is next to impossible.....hands on is the best approach but in this case it's impossible.

As a rundown of what we know:

-bike has 32,000 kms on it
-it developed an issue with 5th gear of which the mechanic said some parts were broken (what parts-shifter fork?)
-transmission was fixed, and bike started and ran?
-bike developed a hard start issue where the battery appeared dead-wouldn't crank engine
-battery was changed to no avail
-starter clutch was changed to no avail
-bike still wouldn't start
-dealership tells you the crank bearings are worn out along with the crankshaft journals which is causing the engine to bind......dealership also tells you 32,000kms are a lot and are pushing you towards a gen 3......go figure.....

Pictures provided of the crank and bearings don't look worn out.

I take it the oil change intervals were followed and no shavings were found in the oil....I also take it there was no loud noises coming out of the engine?

Did the bike overheat.....really overheat to the point it shut down?

What does the clutch pack look like?

Alright going to answer all your questions one by one

1. Bike has 35000km
2. Wouldn’t shift below 5th. The transmission was fixed but post that developed a hot start issue (wait 20 min after a ride to start again)
3. Correct
4. Correct
5. Correct
6. Bike would only cold start , would start even if hot only if I waited for 20+ minutes.
7. Correct
8. Engine was running perfectly( rode it to the service station)
9. It did overheat even when I was riding it but never upto the point that it would shut down.
That was because the coolant tank was cracked , it was repaired and filled with coolant post that it wouldn’t overheat but the problem stayed.
10. I have not had a look at the clutch pack.

 

[jellyrug]

Ryan, I feel your pain. I'm one of those guys who will freak out if anyone else touches my bike in terms of repairs or maintenance. I also read here often about bike modifications and tuners followed by catastrophic results. Then occasionally I help someone who got 20hp extra from a tuner and 10,000 miles later the bike has lost 30% of its power.

Don't believe the "Busa hot start issue" as normal. You can google just about any motorcycle brand from the BMW S1000RR to Triumph, to Yamaha to a Ducati, etc., and you will find a ton of listings where folks are trying to figure out why they have a hot starting problem. This is not normal and there is a fault, or intermittent fault which needs repair. Maybe Google at your end is different to here, as you are in India?

When we get problems like this, there is a systematic way we go about things, fault finding without replacing parts. The electrical process is simple and easy, if that comes up clear, it gets a bit more complex and we have to start taking things apart and test further as well as inspect components.
It is not necessary to replace a battery to see if it makes a difference for example. There is a standard way first to load test a battery and further there are tools available that would immediately tell you how much amperage the starter is drawing, should the bike have difficulty with turning the motor. Those two tests will tell you if the battery is eliminated and further inspection is needed.

It is hard to say from the picture, but the crank bearings to me don't look good. Also, from the crank in case picture, it appears as if there is bearing separation material visible, which is of concern. We need to understand what caused your 5th gear to lock up. That is not normal for a Gen2. If your bike overheated as you say, that is really bad news.

Did you purchase the bike new? Has any modifications been done? What fuel has been used? Were there regular oil changes, and what was the lubricant?

At the end of the day, you are in the hands of your mechanic and if you do not have faith in him, best is to find a different repair shop with good references. All that said, you will find it hard to get a good mechanic to listen and learn from a motorcycle forum.

 

[Ryan Utah]

Thank you so much my man.
All the love to you.
Well if the bearing and the crankshaft looks good then should I just repack the bike and get it back home?

First of all, that Was a very good explanation, and helps alot.
Ok, you have the Hayabusa hot start issue...and that is All.
There is Nothing mechanically wrong with the engine.
Those crank bearings in the picture, are as said, they are ok. They clearly have Not spun, which they have to do if they had 'stuck' or seized to the crankshaft.
Furthermore, assuming the bearings had stuck to the crank, the crank would still Not need replaced.
The crank journals would need machined/milled smooth again to the next size, and oversize bearings would be used, as this is standard procedure, and much cheaper.
So again, there is nothing wrong with the engine.
As for the fan into the coolant resivoir, it sounds exactly as you said, the previous mechanic left bolts loose.
As far as just changing crank bearings, there is no harm in that, but more so...there is no need to.
I would tell them to put it back together and 'fix' nothing else.
As for the transmission; did they ever say exactly what was wrong, or show you old/bad parts?
And, the hot-start issue only showing up after the transmission work may still be a coensidence.
Unfortunately, there is no 100% known cause of the hot-start on the Busa, and it is hard to find since it does not always happen.
The only part that I would personally change would be the regulator/rectifier.
They do commonly go bad, and they can cause strange electrical problems.
There was also a couple of recalls on them on earlier model gen2's.
Will this fix the problem? Most likely not, but at this point, through process of elimination, that is one part that does not hurt to replace, as there is no way to accurately test them.
And if you are unfamiliar with the regulator/rectifier, it is the cast aluminum gray box with cooling fins and one plug going into it, and is mounted under the rear shock and swingarm.
Otherwise, get your bike home, and stay tuned, we'll help you figure out the rest

 

[Ryan Utah]

Ryan, I feel your pain. I'm one of those guys who will freak out if anyone else touches my bike in terms of repairs or maintenance. I also read here often about bike modifications and tuners followed by catastrophic results. Then occasionally I help someone who got 20hp extra from a tuner and 10,000 miles later the bike has lost 30% of its power.

Don't believe the "Busa hot start issue" as normal. You can google just about any motorcycle brand from the BMW S1000RR to Triumph, to Yamaha to a Ducati, etc., and you will find a ton of listings where folks are trying to figure out why they have a hot starting problem. This is not normal and there is a fault, or intermittent fault which needs repair.

When we get problems like this, there is a systematic way we go about things, fault finding without replacing parts. The electrical process is simple and easy, if that comes up clear, it gets a bit more complex and we have to start taking things apart and test further as well as inspect components.
It is not necessary to replace a battery to see if it makes a difference for example. There is a standard way first to load test a battery and further there are tools available that would immediately tell you how much amperage the starter is drawing, should the bike have difficulty with turning the motor. Those two tests will tell you if the battery is eliminated and further inspection is needed.

It is hard to say from the picture, but the crank bearings to me don't look good. Also, from the crank in case picture, it appears as if there is bearing separation material visible, which is of concern. We need to understand what caused your 5th gear to lock up. That is not normal for a Gen2. If your bike overheated as you say, that is really bad news.

Did you purchase the bike new? Has any modifications been done? What fuel has been used? Were there regular oil changes, and what was the lubricant?

At the end of the day, you are in the hands of your mechanic and if you do not have faith in him, best is to find a different repair shop with good references. All that said, you will find it hard to get a good mechanic to listen and learn from a motorcycle forum.

So to be honest my bike has been well maintained.
Never abused.
It’s just heartbreaking for me.
I had a couple of days for my vacation back home and it’s just been sad and depressing ever since this incident.
I hope we all get together and find a solution.
Also I asked him about the rectifier he said it’s working ok.