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Discussion Starter #1
So heres what im dealing with. Any help would be appreciated, ive rebuilt numerous 450r's this one has me stumped. I replaced the starter clutch, new pro x piston and rings, re seated the valves, shimmed to spec, timing marks are on and gas is going to the head and still no start.
 

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Is it turning over or doing nothing? I assume you adjusted the decompression mechanism, checked cranking compression, and spark. Could be the main fuse blew out if the bike is doing nothing. If it’s making a whining noise it could be the reduction gear for the starter clutch but I assume you took a look at that as well. If it’s trying to fire but won’t I’d double check everything one more time.
 

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Discussion Starter #3
Getting good spark, has good compression, decompression is within spec. Replaced one way bearing and gear.
 

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Hey Gents, reading a lot on this no start after clutch replacement and what a great job you all have done!! And guess what, I got the same problem and all timing, ignition, fuel has been checked and verified.
Has any one solved this no-start after this repair?? All timing marks are dead on the money the T mark sets the lower gear alignment with the balance shaft with the gear large hole locates the crank shaft splines, seems straight forward.... The balance shaft runs the oil pump, so I do not see any valve timing relation and I'm possibly incorrect. Any direction would be greatly appreciated.
 

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Getting good spark, has good compression, decompression is within spec. Replaced one way bearing and gear.
Newlands make sure your starter clutch isn’t on backwards as well. Look at TRXONT’s photo if yours looks like that it on backwards. If it’s not on backwards I’d check some sensors and bypass them as needed, could be broken woodruff key as well, and I’d pull of the starter clutch reduction gear and make sure clip isn’t sheered
 

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Looking at more it seems like the starter clutch that you have TRXONT isn’t the oem starter clutch it looks similar from the back but I don’t think you can install the starter clutch backwards making me think it’s a different type starter clutch maybe a eBay replacement? I don’t know but I do know you can install the one way bearing backwards causing the sprang not to engage on the starter clutch so it will only turn over.....make sure you have it on correct same for you Newlands
 

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Thanks cumminstrx for the reply, very much appreciated!!! The after market assembly has a different outer gear design (Threw me for a loop as well when I opened the box), see pics attached of the original design the inner outer gear looks identical to the after market outer gear seen in 1st first picture in original message. The complete assembly cannot be installed incorrectly, there isn't enough room, the outer small gear can be reversed and will hide the timing witness mark (dot). Lots of compression, fuel, spark (new OEM plug) will keep plugging along...
 

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Thanks again, On the original spraggs the blue dot must face OUT against the snap ring, if you have it apart for some reason, or the clutch will work the opposite as designed. It cranks over mint, no problems like before the reduction gear would just spin not the engine. Ran perfect when it did crank over before repair...
 

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newlands97- Did you get anywhere with [U]cumminstrx[/U] recommendations or anywhere else??
I had a crank no start issue with one of those cheap aftermarket starter clutch assemblies. I found out that mine wasn't disengaging when it was supposed to. I went to pop start it, and I heard a crazy loud starter whine. It would crank really well on the starter, but never actually fire up.

Try popping it and see what happens? If you hear the starter motor whine loudly, your starter clutch isn't disengaging.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

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Awesome, Thank you. I also installed an after market unit, I'm in the middle of reinstalling the original intermittent clutch assembly too see if it will start.
 

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Discussion Starter #15
Thanks guys im going to tear back into it today and see what ive done wrong. Hopefully positive Updates to come.
 

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Hey, got mine running!!! I took phillybuilts post and reinstalled my original Honda part started first push of the button! Here is the diag I did:

crankshaft timing marks "T" top dead center
balance shaft timing marks TDC with starter gear marks (see pictures)
valve timing will not change unless you moved timing chain, loosen tensioner
verified fuel deliver, choke on, no throttle activation
spark testing tool during crank verifying ignition spark
compression test, 50 psi

The non OEM clutch was preventing the motor from firing as the crank speed is too fast, there is a significant difference in the crank speed sound and pulse from spark tester results from the original non Honda assembly.

The clutch sragg height and over all design seems compatible, but is not this was a purchase from amazon that I'm returning this kit (
The overall results was the idle gear was deflective, clutch was not the problem. If you just replaced the spragg assembly there is a orientation that requires the painted dot pink/blue has to face out!!
There is multiple people having the same symptoms after this repair and the forms correspondence stops at some point with no one sharing there completed results. Phillybuilts responded to the trend and worked for me...I thank this person dearly for the direction.

The non OEM is the assembly on the left

If there is anything else I can assist you with, please advise.
151653
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Very happy I could help!

One thing I have found, is that the gear that the spragg rides in, the face where the spragg rollers contact will wear away over time. Mine was freewheeling with a brand new starter clutch spragg installed.

Moral of the story: save up for new OEM parts and fix it right the first time!

Sent from my SAMSUNG-SM-G935A using Tapatalk
 
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