Author Topic: honda s90  (Read 8618 times)

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Offline 02z06dave

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Re: honda s90
« Reply #25 on: August 29, 2017, 02:06:46 PM »
Good to hear you got her fired-up  :)
I would clean the tank out too otherwise any little bit of sediment in the tank will feed directly into your  jets w/ a never ending job of cleaning out the carb.

Thanks. I actually did clean the tank already, it had some surface rust. I was just lazy and didn't check the petcock.

Offline 02z06dave

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Re: honda s90
« Reply #26 on: September 08, 2017, 03:48:58 PM »
I had been messing with the carb trying to get this thing to run better. It was running very weak, no power at all (not that it has much to begin with). I took it for a little spin and right when I got back, it died followed by a loud bang out of the exhaust. I couldn't get it to start again and compression felt non existent. A compression check showed a nice 0. I popped the head off and found this...



The carb needle that was missing when I got the bike. I guess the PO lost it in the engine somehow. I guess that will certainly cause an engine not to run well. I'll be doing the top end now before selling it.

Offline MoMo

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Re: honda s90
« Reply #27 on: September 08, 2017, 05:03:09 PM »
Wow,  how badly damaged is the valve seat?

Offline 02z06dave

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Re: honda s90
« Reply #28 on: September 08, 2017, 05:28:40 PM »
 Not sure, I haven't gotten that far yet

Offline Stev-o

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Re: honda s90
« Reply #29 on: September 08, 2017, 07:10:50 PM »
Oh #$%*e!      Damn PO's.....
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Offline jgger

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Re: honda s90
« Reply #30 on: September 08, 2017, 08:02:17 PM »
Maybe he subscribed to the practice of "any left over parts, just drop them in the carburetor........they will find a home"!

That sucks though. Is there a needle in the carb slide? Or was that just an "extra" one ? How does the top of the piston look?
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Offline 02z06dave

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Re: honda s90
« Reply #31 on: September 09, 2017, 04:35:53 AM »
Maybe he subscribed to the practice of "any left over parts, just drop them in the carburetor........they will find a home"!

That sucks though. Is there a needle in the carb slide? Or was that just an "extra" one ? How does the top of the piston look?

I bought a new needle when I first got the bike, so there is one in the slide. I checked to make sure. This was the original needle that was "missing". The top of the piston looks fine. It just had small metal chips on it. I'm sending the cylinder to dratv for their "big bore kit". The piston skirt is worn badly with deep gouges. The cylinder didn't look as bad, but I figured, "what the hell". It's got over 20k on it, it's probably time. And it's cheap.

Offline 02z06dave

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Re: honda s90
« Reply #32 on: September 22, 2017, 07:30:09 AM »
I ordered parts to rebuild the head and just got it torn down. I bought valve seals that say they're for the s90, but upon disassembly of the head, I found there were no valve seals there to begin with. Did the early models not have seals? I know other models of the era didn't have valve seals, such as the superhawk.

Offline grcamna2

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Re: honda s90
« Reply #33 on: September 23, 2017, 11:57:47 AM »
I ordered parts to rebuild the head and just got it torn down. I bought valve seals that say they're for the s90, but upon disassembly of the head, I found there were no valve seals there to begin with. Did the early models not have seals? I know other models of the era didn't have valve seals, such as the superhawk.

I just looked on a microfiche and it does show a valve seal(part#14730-028-013)for each valve stem of the Super90.
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Offline Scott S

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Re: honda s90
« Reply #34 on: September 25, 2017, 04:18:57 AM »
 There were quite a few running changes with the S90 (and CL90). This website helps make sense of some of them.

http://s90partspuzzler.blogspot.com/
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Offline 02z06dave

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Re: honda s90
« Reply #35 on: September 25, 2017, 04:30:36 AM »
There were quite a few running changes with the S90 (and CL90). This website helps make sense of some of them.

http://s90partspuzzler.blogspot.com/

Thank you Scott! That's very helpful. So if I understand that correctly mine would not have an exhaust valve stem seal since it is before the frame number listed. There was no mention of an intake valve stem seal, no I'm assuming it doesn't get one either. I noticed the gasket and seal kit I bought only case with 1 valve stem seal. So I guess that would be for the exhaust valve on later bikes.

Offline Stev-o

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Re: honda s90
« Reply #36 on: December 19, 2020, 06:35:11 AM »
Hey guys....just bought one of these for my daughter, it’s a cute little toy!

PO was riding it with no front brake, it just needed an adjustment!   Cable is way too long, looking for another. 

Seems most parts for these are from Asia, I’d like to avoid that.  Has incorrect taillight too, huge for this little bike!

Overall, it's in pretty good cond, it does start right up but have not had a chance to check everything out yet.

Raining out today, so heres a crappy garage pic. 





« Last Edit: December 19, 2020, 10:41:42 AM by Stev-o »
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........