Honda Motorcycles - FireBlades.org banner
1 - 20 of 33 Posts

·
Registered
Joined
·
63 Posts
Discussion Starter · #1 · (Edited)
So got a few finally things fixed and rode my RC for the first time this weekend. Bike sounds great revin it up and idling with the clutch held in. No motor noises at all. If I put the bike in nuetral and let off the clutch, every 5 or 6 seconds in the idle you can hear a slight what i would describe as a tap, clutch in and it goes away.

Now riding the bike, 1st gear is perfect, shift into second, the bike doesnt jump out of gear or any stumbling whatsoever but makes a terrible banging noise, im talking loud jackhammer, like one of the pistons is about to bust through the case. Shift to third and no noise, no problem. All of the other gears work perfectly. The bike never pops out of gear but I am obviously skipping second gear because I do not want to further damage whatever it is that seems to be messed up. Any ideas? Im thinking that the 2nd gear is shredded and Im going to have to split the case, i'd assume that if the gear was missing teeth it would jump out of gear or just not move very smoothly but it does? It goes just as smooth as any other gear just sounds like something is terribly wrong... Any suggestions.
 

·
Registered
Joined
·
656 Posts
Hmmmm............. Since there is an other guy here who just reported tranny problems recently you must be the second ever!

It sounds like a broken gear! The teeth on the gears don't engage, they are constantly engaged (hence constant mesh gear box) either the driven or the driving gear slides against the shaft and are coupled with the gear next to it by holes on their sides or dogs against the holes of the gear next to it.
Those dogs have a slight negative slope so they suck up against each other once engaged. The other guy's comment was indicating jumping out of 6th, which means that slope is warn. In your case the problem sounds like teeth that are broken, chipped, and bind against the teeth of the opposing gear.
As I said to the other guy be really careful as an other small piece will find each way between the teeth and lock the rear wheel while riding till the cases crack or you are skidding down the pavement.
With a thrown rod you may have enough time to pull in the clutch. With a broken gear it makes no difference the rear stays locked all the way to the shop!
 

·
Registered
Joined
·
134 Posts
yes here i am, the other guy with tranny trouble. your problem sounds worse than mine. i wont say im a transmission expert, other wise i would not have posted a thread. but a friend of mine had the same trouble as you, but with a Suzuki SV 1000 s, also a v-twin. same story with the 2nd gear. but his tranny trouble started because he abused the bike, by wheeling the bike in 1st and then violently snapped the bike into 2nd while the front wheel was in the air. im not sure if that was the life your bike experienced. my feeling is that there might be a bearing busted somewhere.
please keep me posted on whats happening, maybe we can assist each other along the way?
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #4 ·
Well... When I got the bike, the fork seals were so shot that there was a puddle of fluid on the floor of my garage under my front tire, So I'd say the kid I bought it from was beatin it pretty good. Granted thats what bikes like this are for but obviously he had a bad shift or two into second to cause this type of issue. I think I am going to pull the oil pan and see if there are any foreign objects in my oil. With the bike on a jack, I may be able to see the trans gears with the case open to verify what exactly looks messed up. Gonna get to that this weekend. Gotta clean up my workbench and my garage to get ready to tear the motor apart... Anything else I should look for once its opened up or you guys would suggest replacing? My last bike was a 2000 Superhawk 996 so I a familiar with Vtwins but the RC51 is obviously a whole different beast.
 

·
Registered
Joined
·
168 Posts
If you're going to pull the engine, also check the shift forks if they're straight or have discoloration on the sides.
Since it sounds like the bike was abused.
The previous owner (the kid) may have bent a shift fork banging shifts.
And check the slots and dogs for wear.

By comparison, my '02 has 49K miles on it and shifts smooth as silk.
One of the best gearboxes I've ever used.
I hate seeing excellent machinery abused by idiots.
It's the gearhead in me...
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #9 ·
Tore into the engine today... what did I find, a tooth from my second gear in the pan. From what I can see the gear with the missing tooth is the only damage. Im wondering if theres a way to only drop the lower part of the motor, replace the trans shafts and pop it back in. Im going to end up pulling the whole motor regardless but it looks like you could just drop the bottom half. Anyone know of any instructions posted to do the timing once I get it all back together?
 

·
Registered
Joined
·
656 Posts
Hmmmm..........

In your case the problem sounds like teeth that are broken, chipped, and bind against the teeth of the opposing gear.
I hate to be right sometimes! Your next concern is why did that tooth break off. It is nt very common but it seems very unlikely that it was a manufacturing fault. Take everything apart very carefully and inspect every part to assure there is not something else broken in there which allowed a piece to go between the two gears and cause one to break. Also there should be some evidence of the damage to the opposing 2nd gear from the break and from uneven wear which will affect the new one, so you'll probably have to change the set of 2nd gears.
Look for more pieces and don't assume they all came from that tooth.
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #13 · (Edited)
Yep my thoughts exactly... I did find a few small metal shards in the oil pickup screen. Obviously once the motor is apart I can take a close look at all the internals..

My bike has 25,000 miles on it, and like I said the kid I bought from was definitly wheelying the sh*t out of it, (Had to replace the fork seals, they were so bad that there was a puddle of fluid under the front tire) So its not surprising to think that he was bang shifting with no clutch or who knows what else... I found a set of complete trans gears with about 8,000 miles on them from a parted RC51 from a shop, so Im just going to replace both trans shafts. This way all of the components are the same wear. Not brand new, but way lower mileage than my 25k.
 

·
Registered
Joined
·
30 Posts
Mate, I had exactly the same thing years ago on my old GSXR1100K , I pulled the engine apart and 2nd gear had chips off the edge corners on the gears.New 2nd hand box fitted and was sorted, I think to many 2nd gear wheelie's caused the prob..:idunno:
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #17 ·
Split the case open... Second pic shows the missing tooth on 2nd gear. My replacement trans shafts should be here by mid week and I have to order a couple gaskets then I can put her back together. First I have to clean the hell out of everything
 

Attachments

·
Registered
Joined
·
63 Posts
Discussion Starter · #19 ·
Ebay is worldwide my fellow RC51 enthusiast! If youve got the internet, you're pretty much good to go. I picked up both complete trans shafts on ebay slightly used in mint condition (8,500 miles on them) for $49.99 plus $14.00 shipping. In total I had to buy a gasket for the stator cover ($15) and I have to fabricate a Lock nut socket ($10) to retorque the motor mounting points. The total teardown and repair of my transmission is roughly $90.00... not counting my personal labor of course (a couple weekends) which is more of a learning experience in my opinion, but gives me that much closer of a relationship to my RC51...:thumb:
 

·
Registered
Joined
·
1,645 Posts
Ebay is worldwide my fellow RC51 enthusiast! If youve got the internet, you're pretty much good to go. I picked up both complete trans shafts on ebay slightly used in mint condition (8,500 miles on them) for $49.99 plus $14.00 shipping. In total I had to buy a gasket for the stator cover ($15) and I have to fabricate a Lock nut socket ($10) to retorque the motor mounting points. The total teardown and repair of my transmission is roughly $90.00... not counting my personal labor of course (a couple weekends) which is more of a learning experience in my opinion, but gives me that much closer of a relationship to my RC51...:thumb:
My 4th is gone. I need to learn to tear my 954s heart apart and renew her tranny. this is motivation. If my sister was here id just watch her do it lol.
 
1 - 20 of 33 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top