FXR150 conrods breaking

[bucketracer]

It's a mute point in the rules

"Engines must be derived from non-competition motorcycles. Motocross, Road Racing, Enduro and Go Kart motors and transmission parts are not permitted.

If it's OK to change the piston, surely it's OK to change the rod?

This will be an interesting discussion!!!!!!

Corect me if I am wrong, but a rod is an engine part right!!! and so special compition rods are excluded regardless who makes them. Re recent Boysen dual reed thread.

The FXR's look like they have a fatel flaw that will afflict all of them eventually.

The only Bucket legal (sprit of buckiting) way is to find a better rod from some other road bike or hand make them like Burt Munro did.

I recon I could hand make one if I needed too.

Having Wiesco make a batch is a money arsed copout.

.

[Rick 52]

I would love to run a 2 stroke 'to me they are true race bikes but much harder to ride 'A GP in a RS frame is the way forward I think 'and I am saving up now .

[Kickaha]

I hadn't thought about the rods on that fxr150 site good point I'm putting a protest in now

Put in as many protests as you like, they are Suzuki genuine parts so it wont do you any good

[Buckets4Me]

The rod I got from them was a Suzuki rod, there's nothing special about them

had a look and they are genuine parts therefore legal

sounds like the other meltdowns where due to not building replacing the engines right not the rod being shoddy just old
or just maby the engine was over reved like crazy once or a dosen times


Wiseco pistons are ok but rods arn't as they are engine parts
pistons carbs being open as long as they arn't over the cc limit

[Sideways Sam]

Corect me if I am wrong, but a rod is an engine part right!!! and so special compition rods are excluded regardless who makes them. Re recent Boysen dual reed thread.

The FXR's look like they have a fatel flaw that will afflict all of them eventually.

The only Bucket legal (sprit of buckiting) way is to find a better rod from some other road bike or hand make them like Burt Munro did.

I recon I could hand make one if I needed too.

Having Wiesco make a batch is a money arsed copout.

.

I reckon making one is a good option but there's a good chance that it would be possible to get a rod that fits out of another road bike. I'd trust something made in Japan a helluva lot more than something made in Thailand

Actually, I think the bikes are assembled in China by Lion Motor Company! If it's anything like Lion beer it'll all turn to crap overnight..........

The rod specs are as follows if anybody knows of something that might fit. Length can easily vary by a few mm as can the top end width, everything else needs to match though:

Big End Dia = 38mm
Little End dia = 16mm
distance between centres = 102.5mm
Width at Big End = 17mm
Width at Little End = 18mm

Pin Dimensions = 30 x 53???

Buggered if I know how to work out the big end bearing specs, haven't managed to get that far into my engine yet, need special tools.

[Buckets4Me]

Put in as many protests as you like, they are Suzuki genuine parts so it wont do you any good

All talk dont listen to me
just making waves pluss I was miss informed about them being special rods HAHAHA fool on me

[Buckets4Me]

I would love to run a 2 stroke 'to me they are true race bikes but much harder to ride 'A GP in a RS frame is the way forward I think 'and I am saving up now .

ride mine first they are SMALL!!!!!!!!!!!!!!!!!!!!!!!!!

take up Yoga first

[bucketracer]

I reckon making one is a good option but there's a good chance that it would be possible to get a rod that fits out of another road bike. I'd trust something made in Japan a helluva lot more than something made in Thailand

Actually, I think the bikes are assembled in China by Lion Motor Company! If it's anything like Lion beer it'll all turn to crap overnight..........

Right on, I hope something suitable can be found. I am looking forward to getting my TF100 out there and humiliating some of those FXR's if there are any left running by then.

Secretly my TF would like to be a FXR when it grows up.

[Sideways Sam]

had a look and they are genuine parts therefore legal

sounds like the other meltdowns where due to not building replacing the engines right not the rod being shoddy just old
or just maby the engine was over reved like crazy once or a dosen times


Wiseco pistons are ok but rods arn't as they are engine parts
pistons carbs being open as long as they arn't over the cc limit

Just cause it's made by Suzuki doesn't mean it's not a race part.... They have a whole division dedicated to manufacturing race parts.

If they're not standard FXR parts they are race parts (aren't they?). The way I've had it explained to me by some Mainlanders is that the parts they are buying are racing parts.........

The way I read the rules, as long as your engine is "derived" from a non-competition engine and you're not using competition parts in your transmission (I think that is referring mainly to clutches) then just about anything else is OK.....

I might ask MotorcyclingNZ to clarify the conrod thing. I know there are a helluva lot of buckets that don't have the standard rods in them. I'm rather keen to follow the rules, hence the all the mudguards and chainguards etc (and no kickstart) on my bike.

[Skunk]

If they're not standard FXR parts they are race parts (aren't they?).
The way I read the rules, as long as your engine is "derived" from a non-competition engine and you're not using competition parts in your transmission (I think that is referring mainly to clutches) then just about anything else is OK...
I might ask MotorcyclingNZ to clarify the conrod thing. I know there are a helluva lot of buckets that don't have the standard rods in them. I'm rather keen to follow the rules, hence the all the mudguards and chainguards etc (and no kickstart) on my bike.

I don't think MNZ would even know what you asking about - they wouldn't know a Bucket if they fell over one.

'Aftermarket' does not mean 'Racing'. Most Buckets have aftermarket parts as soon as they get rebuilt the first time.

The engines are derived from road-going bikes; that's all that really matters. If you're clever enough to fit an aftermarket rod from some other bike (R6 or some such) good on you.

[TZ350]

I know there are a helluva lot of buckets that don't have the standard rods in them.

It does not have to be a standard (original) rod but a rod derived from any road bike, I have been using RD400 rods because I have a number of them in my bucket of bits, unlike the original they have slotted big ends and can run silver plated RG big end bearings. They are also longer than the std, rod and with a thick cylinder spacer add usefully crankcase volume.

[TZ350]

I would love to run a 2 stroke 'to me they are true race bikes but much harder to ride 'A GP in a RS frame is the way forward I think 'and I am saving up now .

Bugger, if Rick gets one of those he will be impossible to catch. Hope he is just trying to frighten us.

[Sideways Sam]

I don't think MNZ would even know what you asking about - they wouldn't know a Bucket if they fell over one.

'Aftermarket' does not mean 'Racing'. Most Buckets have aftermarket parts as soon as they get rebuilt the first time.

The engines are derived from road-going bikes; that's all that really matters. If you're clever enough to fit an aftermarket rod from some other bike (R6 or some such) good on you.

I'm with you on that. I think the intention of the rule is that we aren't running CRF150R motorcross motors or similar......

The whole idea of a Formula is that you can modify the engines etc, that's half the fun of it...... I don't even ride the bike, I just make it go as fast as I can for my son (who seems to have no fear!)

[Bren_chch]

In my experience the rods seem strong, but the end bearings could be a weak point.

The FXR engine I built that won the BOB was bought as a dead engine which had been run out of oil... it had stuffed the cams and pretty much the complete top end, i rebuilt with, Longer duration cams, raised compression, ported head, flatslide carb, new CDI with better power delivery and no rev limiter, spanky header pipe and muffler... the bike was a ROCKET and i'd guess it was about 18 - 20hp and it went well for a while till it dropped the end beaings, not the rod but the end bearings... which was bound to happen eventually given the state i bought it in... i stuck in a new rod kit and it won the BOB and its never missed a beat since. it now gets some serious abuse from its new owner!

This is the first time i have seen an actual broken rod!

Good work dangerous!!!

If a rod has broken then something else has failed to cause this. Rods dont break like that on engines that are in the bucket hp range, generally something would have to have stopped the rod/piston from moving in whatever direction it was going.

I would like to know what sideways did to his topend that made his rod break i the time it did. can you share?

[Sideways Sam]

In my experience the rods seem strong, but the end bearings could be a weak point.

The FXR engine I built that won the BOB was bought as a dead engine which had been run out of oil... it had stuffed the cams and pretty much the complete top end, i rebuilt with, Longer duration cams, raised compression, ported head, flatslide carb, new CDI with better power delivery and no rev limiter, spanky header pipe and muffler... the bike was a ROCKET and i'd guess it was about 18 - 20hp and it went well for a while till it dropped the end beaings, not the rod but the end bearings... which was bound to happen eventually given the state i bought it in... i stuck in a new rod kit and it won the BOB and its never missed a beat since. it now gets some serious abuse from its new owner!

This is the first time i have seen an actual broken rod!

Good work dangerous!!!

If a rod has broken then something else has failed to cause this. Rods dont break like that on engines that are in the bucket hp range, generally something would have to have stopped the rod/piston from moving in whatever direction it was going.

I would like to know what sideways did to his topend that made his rod break i the time it did. can you share?

12.5:1 compression with the help of a different piston and 0.9mm squish
Standard Cams and Cam timing
Head flowed with 11% better flow
Standard Carb and airbox (rejetted)
Standard CDI (with rev limiter) etc
Running on race fuel
Will let you know the damage when I get her pulled down, that'll be after I get over the hangover from tomorrow night.....

Was running like a rocket ship, sounded like a Motard (maybe the extra compression?) The difference in bottom end torque was phenominal, if I'd had enough time to get the jetting right it would have been really impresive.....