CRF bottom end assembly help?

[CHOPPA]

Hey guys im just putting my crank back in my 2008 CRF450.

I have the cases together but not torqued up.

Now im not missing any parts but the crankshaft is moving a couple millimetres side to side within the the cases.....

This doesnt seem completely right to me but it maybe it is? Maybe when I put the stator on and the output gear etc it might tighten up?

Anyone have any experience? I dont want to get to far into it before im 100%

[CHOPPA]

I think I found the answer to my question here but still keen to hear your thoughts...

http://www.crfsonly.com/forum/viewtopic.php?t=26923&postdays=0&postorder=asc&start=15&sid=8ca5a5ba74b66e8d61251f09ebb6a596



(http://www.crfsonly.com/forum/viewtopic.php?t=26923&postdays=0&postorder=asc&start=15&sid=8ca5a5ba74b66e8d61251f09ebb6a596)

[barty5]

Just rebuilt one this week and yes you will need to make sure the bearings are around the right way there is a step in the out side edge of the right side bearing that the lock tabs fit over to hold it in. and make sure you dont leave out the little one way valve ting at the bottom rectangular shaped thing.

[CHOPPA]

Just rebuilt one this week and yes you will need to make sure the bearings are around the right way there is a step in the out side edge of the right side bearing that the lock tabs fit over to hold it in. and make sure you dont leave out the little one way valve ting at the bottom rectangular shaped thing.

Thanks man, yeah I had to replace that reed valve thing cause i damaged it when i split it. Bearings and tabs all in minta :)

[CRF119]

How Many hours had your CRF450 done before it needed big ends?

[CHOPPA]

60 is all id do on a crank

[CRF119]

Lol. 60 why so low? I consider my self to be a pretty good rider and by no means has my CRF been nanerred around and my bike is sitting on 170 hours and all ive done is timing chains and pistons. Even the valves are still in spec.

[barty5]

Lol. 60 why so low? I consider my self to be a pretty good rider and by no means has my CRF been nanerred around and my bike is sitting on 170 hours and all ive done is timing chains and pistons. Even the valves are still in spec.

go for a ride with chop an see if you keep lol

[CRF119]

go for a ride with chop an see if you keep lol

One day given the oppertunity ill take that offer. I need somebody to chase on a trail ride. Im a winter MXer so will have to be then.

[CHOPPA]

Lol. 60 why so low? I consider my self to be a pretty good rider and by no means has my CRF been nanerred around and my bike is sitting on 170 hours and all ive done is timing chains and pistons. Even the valves are still in spec.

I think on trail rides etc it is way to low, short track racing is much harder on the engine because the hours that it does do are at much higher revs. Hour meters are all good, same as ks on a road bike are a good guide but its all guess work. We need something that counts engine revolutions.....

Conrods break on modern 4 strokes and then they eat your entire engine, better to replace and be safe

[CRF119]

So you are more worried about the rod then the bearings? Are you replacing your Honda crank with genuine again or is there some thing better? My Bike is used for everything. At the end of the day i think if it blows up ill be putting a CR500 motor in it :)

[browny]

So you are more worried about the rod then the bearings? Are you replacing your Honda crank with genuine again or is there some thing better? My Bike is used for everything. At the end of the day i think if it blows up ill be putting a CR500 motor in it :)

saw one of those 500's at a club day last wekend. what a weapon. arse to start cold tho.

[CHOPPA]

So you are more worried about the rod then the bearings? Are you replacing your Honda crank with genuine again or is there some thing better? My Bike is used for everything. At the end of the day i think if it blows up ill be putting a CR500 motor in it :)

Yeah for sure more worried about the rod, they break... I honestly havnt looked into other rods, I dont really ride MX anymore....

The 500 would be fun, I have had a few 500s and I dont really like the power delivery. They are really low revving engines and dont have a powerband like you would expect. They are more like a 4 stroke. They are bloody expensive too!! Still a good mod and adds value to the bike if done right.

There is a guy in Tauranga that if you give him $1000 a bike and a 500 engine you can ride it out the shop. Top quality too