2006 Honda CRF450R Broken Cam Chain guide bracket

[74jabr]

The bracket that holds the cam chain guide in place has broken off. The guide is still being held in place somewhat not sure if i should replace left side case?

 

Has anyone seen this happen before?

[HRC27]

The bracket that holds the cam chain guide in place has broken off. The guide is still being held in place somewhat not sure if i should replace left side case?

Has anyone seen this happen before?

It's been discussed here and the advice is to use the correct flywheel puller* for this bike, shield anything you think might be affected by heat and have it welded back on.

* the correct puller has a cap that goes on the crank first to protect the crank end oil port.

Edited October 20, 2016 by HRC27

[TDW]

When that piece is broken the cause is normally because cam chain tensioner didnt hold and the chain bunched up in the bottom area and caused a piece to break.

There are other ways it could possibly break or be broken off.

If someone is trying to remove the flywheel without the proper puller like what was mentioned in a previous post, and a screwdriver or something similar was used to try to pry the flywheel or put pressure on it can also be the cause.

Another possibility might be if someone was trying to manually turn the engine over or kicked it over with the tensioner removed, and the chain jams or bunches up.

I would replace the chain and the tensioner.

Try to get an opinoin from a professional welder or welding shop to see if its possible to get it welded back on.

Edited October 21, 2016 by TDW

[74jabr]

Thank you for your response. I am taking it to a local shop this weekend I'll share this info with them.

 

This is the first time i've taken the cover off so who knows how long it's been this way.

[CarGuy7a]

I'm a Tig welder by trade and weld aluminum every day and I can tell you tig welding on cast is a complete PITA even if it's clean. Especially cast that has been subjected to alot of engine oil. As long as you clean it very well it can be done but I never put too much faith in welding a piece of cast especially a piece that small. Problem with cast is that it is very porous like a sponge and it soaks up load of contaminants in those pores. Even when clean it's almost as if you are welding without gas (very nasty).

 

I'm not saying don't do it but be mindful of what could happen down the road. It could possibly break off again.

Edited October 24, 2016 by CarGuy7a

[Rocksalt]

That does not look like it needs to be welded. As long as the bottom of the guide is trapped it will be OK. I don't think that can be welded as a cost saver anyway for the reasons mentioned above.

 

I have one bike with the same type break. Been running it for 5 years that way

[74jabr]

Thank you agian for all the responses,

I took it to a motor guy last weekend he said the same thing Dont Weld It that there is enough of the bracket left to run it as is.

[dangleebals]

Hey All,

apologies for the thread resurrection but private messaging isn't working for me so couldn't contact 74Jabr directly. I'm in the same position and wanted to know from those that mentioned just run it as it has enough meat there, did it ever fail further down the line?

mine below

 

cheers

Deacs

Edited April 2, 2020 by dangleebals

[Shawn_Mc]

On 4/2/2020 at 2:24 AM, dangleebals said:

Hey All,

apologies for the thread resurrection but private messaging isn't working for me so couldn't contact 74Jabr directly. I'm in the same position and wanted to know from those that mentioned just run it as it has enough meat there, did it ever fail further down the line?

mine below

 

cheers

Deacs

You've got plenty, but Id suggest a manual tensioner. If the OEM chain tensioner allows the chain to start whipping (and it will) it'll probably knock that guide out on the bottom. It's sandwiched in the top, but still not good. Make sure the bottom guard isn't bent out of the way too.

The bottom guard gets bent when the engine gets turned over with the chain down there while messing with something else. Ive seen it more times than I can count.

[dangleebals]

On 4/5/2020 at 8:53 PM, Shawn_Mc said:

You've got plenty, but Id suggest a manual tensioner. If the OEM chain tensioner allows the chain to start whipping (and it will) it'll probably knock that guide out on the bottom. It's sandwiched in the top, but still not good. Make sure the bottom guard isn't bent out of the way too.

The bottom guard gets bent when the engine gets turned over with the chain down there while messing with something else. Ive seen it more times than I can count.

Hey Shawn_MC thanks for the reply and info, much appreciated (y) roger that re the manual chain tensioner, when you say bottom guard - do you mean the 'u' piece thats left from the broken area?

[HRC27]

1 hour ago, dangleebals said:

Hey Shawn_MC thanks for the reply and info, much appreciated (y) roger that re the manual chain tensioner, when you say bottom guard - do you mean the 'u' piece thats left from the broken area?

If they ship to the UK, get a Thumper Talk manual tensioner. I have one on my bike and it's very well made.

[Shawn_Mc]

12 hours ago, dangleebals said:

Hey Shawn_MC thanks for the reply and info, much appreciated (y) roger that re the manual chain tensioner, when you say bottom guard - do you mean the 'u' piece thats left from the broken area?

No, the steel piece that bolts onto the case on the very bottom.

[dangleebals]

On 4/15/2020 at 6:53 PM, HRC27 said:

If they ship to the UK, get a Thumper Talk manual tensioner. I have one on my bike and it's very well made.

Thanks for the info HRC27, have emailed them ?

On 4/16/2020 at 5:49 AM, Shawn_Mc said:

No, the steel piece that bolts onto the case on the very bottom.

ok will check, thanks for the info once again Shawn_MC ?

[Shawn_Mc]

This is the bracket I'm talking about. Why Honda put it on the oil pump schematic, I have no idea. Total afterthought is all I can think of. It's number 1.

 

 

[dangleebals]

On 4/17/2020 at 10:50 PM, Shawn_Mc said:

This is the bracket I'm talking about. Why Honda put it on the oil pump schematic, I have no idea. Total afterthought is all I can think of. It's number 1.

 

 

Brilliant stuff, much appreciated Shawn_Mc ? 

I'll check that now.