FXR150 camshaft/head issues

[Bren_chch]

i think the issue with the heads is caused by low oil level at some stage in the engines life, causing something to pick up in the journals, then we get them and service them well but rev the life out of them which causes whatever has been picked up to get worse and worse until it does what you can see in the pics.

also check the seal on the clutch cover side that the crank end goes in to, because if this has gone then oil pressure will drop to the head.

A tkrj rod kit is going to be about $180.00 plus delivery.

[richban]

what sort of oil people are using.

I use the Motul 300v Factory line 10w40. Double Ester goodness and its green.

[Buddha#81:Me]

I use the Motul 300v Factory line 10w40. Double Ester goodness and its green.

Me.....I use Mobil 1 4T. $13 a litre from allied petrolium. I've taken this oil to 1000 race km and tested at the Goughs oil lab with clear results (only had high lead counts due to running av gas). My FXR was previously owned by Sketchy and I've put nearly 4000 race km on it on all fast tracks (ruapuna, levels, teratonga and street meetings). Other than oil changes i've never had to touch the engine inc valve clearances, for a stocker it still goes ok!

[gatch]

How hard is it on these motors to up the oil pressure ?

[Kickaha]

for a stocker it still goes ok!

Especially when you consider what it has to cart around

[woodyracer]

you going to have a muffler that stays on by that stage?

yes...haahh to be honest my bke was running like crap that day, the pegs were too high [hence my skipping along the track} will have the bike sorted for the TRRS......will have either a race cam or piston to hopefully.....cos the HONDA guys have one and on the straight they left me in their dust....

[fi5hy]

Me.....I use Mobil 1 4T. $13 a litre from allied petrolium. I've taken this oil to 1000 race km and tested at the Goughs oil lab with clear results (only had high lead counts due to running av gas). My FXR was previously owned by Sketchy and I've put nearly 4000 race km on it on all fast tracks (ruapuna, levels, teratonga and street meetings). Other than oil changes i've never had to touch the engine inc valve clearances, for a stocker it still goes ok!

Fuck that means I have trashed that bike It should have died by now then

[Damien_Toman]

Interesting. I have played with 2 different FXR engines and both have shown unusual wear on the middle intake cam and head surface. Yours makes 3. I always make sure my oil level is almost spilling out the top. I checked the cam and head after Taupo and it seemed ok but it still seems strange. Sounds like some one has been playing in your engine before you got it with the bolt issues. You really have to make sure the cams spin free when torquing them down. If you want to make it go faster the question is really how much money do you want to spend. I put a $30 2mm oversize standard piston in my engine 156cc still in the rules. Tuned the carb and exhaust and it freshened it up heaps. Or you can do what I am going to do to the same engine and stroke it longer with a standard piston to get the same 156cc but it means splitting the engine and a stroker pin in the crank. Maybe $400 if you do all the assembly work yourself. Then you might as well lighten the crank, more dosh.

Were you able to have the standard cylinder re-bored for the 2mm oversized pistons? Did you need a larger sleeve? Do you know if the Raider 150 high lift cams fit? Really appreciate you input. Damien.

[woodyracer]

Were you able to have the standard cylinder re-bored for the 2mm oversized pistons? Did you need a larger sleeve? Do you know if the Raider 150 high lift cams fit? Really appreciate you input. Damien.

raider 150's i thought they were 2 smokers

[Damien_Toman]

Me.....I use Mobil 1 4T. $13 a litre from allied petrolium. I've taken this oil to 1000 race km and tested at the Goughs oil lab with clear results (only had high lead counts due to running av gas). My FXR was previously owned by Sketchy and I've put nearly 4000 race km on it on all fast tracks (ruapuna, levels, teratonga and street meetings). Other than oil changes i've never had to touch the engine inc valve clearances, for a stocker it still goes ok!

Sounds good to me. I might try that. I have been using Motul 10-40 4T (5100, ester, MA, Technosynthese). $65 for 4 litres. I use this same oil in my CRF250R motocross bike (used mainly for trail rides). My cam problem almost certainly goes back to before I raced the FXR (changing the oil after every meeting).

[Damien_Toman]

raider 150's i thought they were 2 smokers

From Wikipedia: "The Suzuki Raider 150 is one of the fastest motorcycles in the underbone category. It uses the same 150 cc (9.2 cu in) DOHC four-valve single-cylinder oil-cooled engine which powers its sports bike ......the Suzuki FXR150."

Damien

[richban]

Were you able to have the standard cylinder re-bored for the 2mm oversized pistons? Did you need a larger sleeve? Do you know if the Raider 150 high lift cams fit? Really appreciate you input. Damien.

Yep standard rebore. Tell the people doing it that it will be getting a thrashing. As far as cams go don't know but would think they would fit as the piston does. But if they are hi lift you might need to adjust the squish valve timing. Don't know. You should try and get a spec sheet for the cam duration lift etc. I would not buy any cam without a spec sheet. If you can get a spec I can send it to my Bro cams are his living. He can give an option. Cheers Rich

[Damien_Toman]

Thanks Richban. I'll have a chat with my local head specialist and see what he thinks. I'll see if I can get a cam spec sheet for your bro' to have a look at.

[Damien_Toman]

.......Bearing Failure:- http://www.engineparts.com/publications/CL77-3-402.pdf

Great info thanks.

[Sketchy_Racer]

The problem with the cams could just be a very simple tolerance runout in some motors.

When the engine is running, the cam surface shouldn't actually be touching the head surface, instead the oil acts a fluid bearing and prevents the surfaces touching.

What would cause it:

1 - Low oil, or low oil pressure at one point in its life. Unfortunately once this process has started you can't stop it and you will end up with the wear that you have there.

2 - Out of tolerance cam or head and cam cap. If there is not enough clearance between the cam and cam, then no matter how much oil or oil pressure there is once the motor heats up and things expand then there will be no where for the oil to fit between the two metals and it will seize.

3 - If it has been apart before and not assembled clean, the slightest amount of crap in there will be all it takes for it to start the deterioration.

Unfortunately not an easy fix, there are different methods to fix it but most would run up well into the $400 mark.

You could probably get away with grinding a lot of clearance between the centre cam and if it still has two other cam support surfaces see how long it will last with just them.