Valve guide material?

[Petri]

My 2005 Euro FJR is having some exhaust valves replaced etc.

Now, the machine shop doing the work is suggesting not using the stock Yamaha replacement valve guides, but instead some after-market phosphorous bronze guides. They are quite a lot cheaper and easier to install.

The machine shop specializes in cylinder head work - that's all they do. So I guess they should know what they are suggesting.

But after googling (better safe than sorry), I became a little concerned, especially after reading this warning.

Thoughts? Experience? What are the FJR factory-installed valve guides made of?

I read elsewhere in this forum that Gen I FJRs apparently tend to wear out the exhaust valve stems and guides. The machine shop owner claimed it's been almost a "known issue" with a number of Yamahas through the years.

I wonder if a properly chosen (different) replacement valve guides could mitigate that...?

 

[Viper Pilot]

The FJR (Gen 1) valve guide problem was caused by valve guide seals that were too tight on some of those early FJR's. The guide material was not the problem.

 

[Ignacio]

I read elsewhere in this forum that Gen I FJRs apparently tend to wear out the exhaust valve stems and guides. The machine shop owner claimed it's been almost a "known issue" with a number of Yamahas through the years.
I wonder if a properly chosen (different) replacement valve guides could mitigate that...?

That was well-litigated here as well as the previous forum many here were at. That's why it's pinned as the very first issue on this forum. Short answer is that there was much speculation (including the bronze/other material issue including destructive testing by one of the forum admins), but I believe consensus in the end is that was valve guide seals. Not quite enough oil to lubricate and that then caused excessive valve guide wear.

It also tended to be less of a problem IIRC in later Gen bikes (i.e. 2005 and 2005.5)

I wouldn't imagine different guides would hurt...or necessarily help. I'd read the thread in its entirety and then make sure whatever valve guide seals you choose are up to the task.

 

[Mihalis fjr]

Tell to the machine shop to install new oem valves and valve guides and the newest valve guide seals and your head will be fine!

 

[redzgrider]

Is it a motorcycle specific machine shop, or a car machine shop doing a motorcycle head? Car biased shops tend to think in car needs. Yamaha spent the money on engineering design and analysis to develop guides that they can trust -- they have no desire to repair a head a second time, or lose customer base over internet reports of failing parts. Admittedly, those OEM guides are pricey -- what are the odds the cheaper ones are of similar quality?

If you do go aftermarket, the write up at https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwj_2_ni-9TUAhWHWCYKHbSWDooQFggxMAE&url=http%3A%2F%2Ffjrforum.com%2Fmisc%2FFJR1300_Cylinder_Head_overhaul.pdf&usg=AFQjCNFfCo1o8DCYqampQZ9m8BxoiY0czw&cad=rjt

is awfully educational.

 

[GoldenLeafBird]

Is it a motorcycle specific machine shop, or a car machine shop doing a motorcycle head? Car biased shops tend to think in car needs. Yamaha spent the money on engineering design and analysis to develop guides that they can trust -- they have no desire to repair a head a second time, or lose customer base over internet reports of failing parts. Admittedly, those OEM guides are pricey -- what are the odds the cheaper ones are of similar quality?

If you do go aftermarket, the write up at https://www.google.com/url?sa=t&rct...sg=AFQjCNFfCo1o8DCYqampQZ9m8BxoiY0czw&cad=rjt

is awfully educational.

I know this is an older topic, but I can't seem to find the original PDF. Would you perchance still have it?

 

[redzgrider]

Had to search, but found it. Trying it as a dropbox uploadFJR 1300 cylinder head overhaul pdf
If the link doesn't work, hit me with an email via message and I'll send it. The file is 1.9 MB, so was considered large at one time, but pretty nominal nowadays.

 

[RossKean]

Had to search, but found it. Trying it as a dropbox uploadFJR 1300 cylinder head overhaul pdf
If the link doesn't work, hit me with an email via message and I'll send it. The file is 1.9 MB, so was considered large at one time, but pretty nominal nowadays.

I just had a quick read through that. Great job and well documented!!

 

[torch]

I wonder if a properly chosen (different) replacement valve guides could mitigate that...?

The 01 to 03 (04 in North America) Gen I engines were somewhat prone to "ticking" caused by excessive valve guide wear, primarily in the #2 exhaust valves. Online forum surveys suggested that this affected about 7% of all engines, and a further ~7% of repaired engines.

As others have noted, the issue was eventually traced to the valve seal. Yamaha had re-used an existing part originally designed for the XJ400 twenty years previous and it just wasn't up to the demand. Reports of "tickers" vanished with the revised seals.

However, Yamaha's engineers did not manage to stumble on the solution until after experimenting with new valve stem material (revised design marked with a dot on the valve face) and when that didn't work out, they tried new valve guide materials with equally disappointing results. I wonder if this half-remembered factoid is behind your mechanic's opinion?

 

[graytaz]

What Torch said. My 2003, new in 2002, had the valve guides replaced twice at around 19K klicks and then again at 26K. The issue was with the exhaust side only. Second time in early 2004 included the updated valve seals and that resolved the issue. Most bikes of the same vintage didn't run into a problem. AFAIK there wasn't any further issues once those new seals were put into the production runs.