Honda CRF450R Supermoto (no longer broken!)

[I Fancy Holidays]

Thankyou loud for thread title!

Here is a little bit of a back story. Yesterday, Sunday the 18/09/2011, I decided to brave the terrible weather and attend a practice day for SupermotoWA and PBAWA. Much fun was had by all that turned up (Pete, your a little girl), there where wheelies, stoppies, highsides, lowsides, wet weather drifting and some dry weather knee draggin motard action. All in all a fun day. Pics here courtesy of Anson

But....
As I start my bike for the last session I notice an odd rattle, I quickly kill switch it and call over some spare bodies and start it again. They stick there ears anywhere and everywhere and then signal me to kill it, "top end" is the verdict. What and end to the day, I trailer it home and put it away. That night I do some research and try to think what it could be, nothing sticks out with the symptoms I have so i'm going to have to open her up.

This is how she looks currently (dont mind the messy garage ):

IMG_0348.JPG

IMG_0349.JPG

While i have it in the garage and in bits, I plan on giving it a good clean and replace any worn out parts I find. Tomorrow night ill be starting by taking it apart and cleaning around the head, hopefully the engine will be able to stay in the frame.

Mark.

PS. Anyone here able to weld aluminum? (I have a small crack in the subframe)

[Loud]

What a second, I don't have a Hon... oh I see, like that is it?

Hope it's back up and running soon.

[Shady7/8]

what so special about the pics?

Did I miss something?
Isn't that where Honda dirtbikes spend most of their time?

[I Fancy Holidays]

So I pulled it apart tonight, damn its dirty.








More dismantling and dirt.



[




Drained the cooling system and removed the radiators, guess what? More dirt!






Anyone know how to get rid of the dirt stains on the ally frame/other bits, i'm worried polishing it will just make it shiny, any suggestions?

[Shady7/8]

CLR?
Scotch brite?
Degreaser?

[deano68er]

Eucalyptus oil

[Yeti697]

Do you know what the rattling is? It could be the cam chain... but just guessing. Pull the head off and get the valves checked also as they are probably getting a little old. The piston/ring should be sweet, but check to make sure there is no slop in the big end bearing. This was fine when the big bore kit went on. Be careful putting the cam cover back onto the head, the bolts are a little tricky to line up and can strip out in the head very easily.

Haha, I think I need to update my avatar now.. first time Ive posted in a while...

[Yeti697]

Also... one of those green scouring pads and jiff works miracles on plastics and the frame. Use steel wool and jiff on the frame if its not coming off easy

[I Fancy Holidays]

Do you know what the rattling is? It could be the cam chain... but just guessing. Pull the head off and get the valves checked also as they are probably getting a little old. The piston/ring should be sweet, but check to make sure there is no slop in the big end bearing. This was fine when the big bore kit went on. Be careful putting the cam cover back onto the head, the bolts are a little tricky to line up and can strip out in the head very easily.

I did the valves about 10 hours ago and exhaust were good, intake were a little off so i reshimmed them. At this point im guessing/hoping its the tensioner. The bike had no problems running or starting just before i noticed the noise so valve problems or autodecomp problems dont seem quite as likely. Whats the easiest way to look at the big end on this? Can it be done with the engine still in the frame?

I dont want to open it up until its much cleaner around the top end, ill spend some time tonight on it.

For those who are wondering, Yeti owned this bike before i did!

[Loud]

Is dropping the motor a big deal? Looks like it's only a couple of cables/wires/bolts away anyhow.

[Thirsty]

What's with all the boxes of tissues in the boxes in the background? You know its a very different thing when a man and woman say they went thru a box of tissues watching a movie!

[Yeti697]

To check the big end bearing - pull off the head, then the barrel so the piston and rod are sticking up out of the crank case. Check for up/down movement. If there is movement, there are problems, and the motor will need to come out, and the crank case split which is probably a mechanics job..

[Uni]

Needs more description of noise?

I've had a timing chain auto tensioner fuck out on mine. Bike ran but the timing chain bounces around and sounds like a novelty size spray can on heat.

It's an easy job to get in and out and you'll see straight up if that's your issue (mine disintegrated in my hands). It was a $50 part IIRC

[I Fancy Holidays]

Is dropping the motor a big deal? Looks like it's only a couple of cables/wires/bolts away anyhow.

True, i might do it anyway. Whats powder coating cost these days?

What's with all the boxes of tissues in the boxes in the background? You know its a very different thing when a man and woman say they went thru a box of tissues watching a movie!

Fapkins

To check the big end bearing - pull off the head, then the barrel so the piston and rod are sticking up out of the crank case. Check for up/down movement. If there is movement, there are problems, and the motor will need to come out, and the crank case split which is probably a mechanics job..

Ill see how i go with the tensioner before i dismantle the engine that much.

Needs more description of noise?

I've had a timing chain auto tensioner fuck out on mine. Bike ran but the timing chain bounces around and sounds like a novelty size spray can on heat.

It's an easy job to get in and out and you'll see straight up if that's your issue (mine disintegrated in my hands). It was a $50 part IIRC

That description is fairly accurate.

[I Fancy Holidays]

The plan isnt to just fix the engine, it was also to take it apart, give it a mint clean and maybe spend some monies on it while im in there.



Screwed the tensioner in and it doesnt want to spring back out, seems like this could be the cause (although when i pulled it out it was close to fully extended).

Do you guys think i should stick with an OEM tensioner or go with Tokyo Mods Cam Chain Tensioner: CRFs Only - Your Source For Honda CRF Parts, Accessories and Information.... Its a manual one (not spring based) so it shouldnt(in theory) ever fail, unless i dont maintain it.

[Uni]

Screwed the tensioner in and it doesnt want to spring back out, seems like this could be the cause (although when i pulled it out it was close to fully extended).

Bingo. Auto tensioner should be 'springing' out all the way.

Do you guys think i should stick with an OEM tensioner or go with Tokyo Mods Cam Chain Tensioner: CRFs Only - Your Source For Honda CRF Parts, Accessories and Information.... Its a manual one (not spring based) so it shouldnt(in theory) ever fail, unless i dont maintain it.

I replaced with stock (cheap and available at the time) but maybe I should have gone after market.

I'm not overly keen on manually tensioning but in light of the OEM auto failing.. I'm not so sure. What's the go for tensioning?

[I Fancy Holidays]

Needs more description of noise?

I've had a timing chain auto tensioner fuck out on mine. Bike ran but the timing chain bounces around and sounds like a novelty size spray can on heat.

It's an easy job to get in and out and you'll see straight up if that's your issue (mine disintegrated in my hands). It was a $50 part IIRC

Do you remember where you got it from, a quick look found thats the best i could get it for online.

I replaced with stock (cheap and available at the time) but maybe I should have gone after market.

I'm not overly keen on manually tensioning but in light of the OEM auto failing.. I'm not so sure. What's the go for tensioning?

The Tokyo Mods website has very little info so i did a bit of googleing and it seems for race bikes, manual is better. Adjustment intervals vary from check/ adjust as often as you do your drive chain, or as often as you change your oil, up to every time you check your clearances.

What worries me is the adjusting seems to be a bit of a by feel thing and id hate to get it wrong.

[Loud]

True, i might do it anyway. Whats powder coating cost these days?

Like mine? About $120. Plus endless hours of preparation and masking. Plus the engine has to be stripped to just the bare cases. Factor in the cases being destroyed and needing to seek replacements too.

...Not great value. Sounds like you've found the issue anyway and won't need to go to all the effort - great news!!

[I Fancy Holidays]

Like mine? About $120. Plus endless hours of preparation and masking. Plus the engine has to be stripped to just the bare cases. Factor in the cases being destroyed and needing to seek replacements too.

...Not great value. Sounds like you've found the issue anyway and won't need to go to all the effort - great news!!

I was more thinking about just getting the frame done, but i can think of much better things to spend the money on.

Ive decided the old catch can has to go, its bulky and looks completely wrong (does its job though). I plan on using a hip flask mounted upside down to the front of the engine/frame. It should fit perfectly and look OK. Ill be redoing all the plumbing associated with it as its currently a bit of a mess.

Im also looking at spending some money on the brakes. Racing pads, shorty leaver, mc res cap, and a caliper rebuild kit. Hopefully ill be able to get it for ~$300 landed.

[I Fancy Holidays]

Dismantled the front end.


Leaky seal.


More dismantlage.



I think im going to get some new springs front and back, new seals, bushes and oil. I also heard back from my beringer guy, i was hoping for $300 landed but it seems its going to be $400 pp for parts mentioned, bit of a bummer.

While i have it apart this much already, do you guys think its worth it to take the carb apart and clean it up? (it was running mint when i dyno'ed it a couple months back)

More to come!

PS. Dazza if your reading this, how did the freezer trick go on your pipe?