WGREGT Posted September 4, 2012 Share Posted September 4, 2012 Just when I thought I was done wrenching, the VFR needs a front tire (I have one here already) and apparently clutch plates replacement. 1st gear is fine when ridden hard to redline, but 2nd gear has it surging and slipping and sometimes grabbing pretty much every time @ 10k before I can get to redline. 3rd-6th is OK, and I can even get 2nd to get to redline occasionally if I get there gradually and not when I'm accelerating hard. The 2nd gear thing feels like someone is taking the spark plug wire off and then putting it back on....power up till 10k, then surging and bucking. I can upshift pretty much from 1st to 6th without touching the clutch lever too by just briefly rolling off the gas. I've also had 2-3k miles of sorta "slingshotting"....I'm behind a car that I need to get around, so I grab a handful of throttle, never touch the clutch, and it sorta spins up the engine noise for a second without much more forward momentum, then catches and slingshots me ahead. It feels like I was losing traction on ice or something where I was spinning the back tire in a straight line, and then it suddenly gained traction. If it was a nitro Busa I could say it was lighting up the rear tire with hp. But it's not. It's a 18 year old, 100 hp bike with 55k on it. I am pretty sure, based on knowing the previous owner, that it's the original clutch plates. 55K on these currently. Granted, I ride this thing hard. Really hard. Pretty much every launch is a hard launch, redline, shift, redline, hard on the gas, etc. I know I should take it easy on the old girl, but it's so much damn fun and sounds so damn good it's hard to resist. So..sound to you like a new batch of clutch plates (steel and fiber all the way around, or re-use the steel ones?) and new springs as well? Do you recommend OEM, Barnett, EBC, others? I plan on tearing it down this week to see if I need JUST the fiber plates, or the fiber and the steel plates. Apparently from what I've been told sometimes you can get away with re-using the steel plates if they are not blued from heat and are not warped (tip: lay them on glass or a mirror to check). So, before I order everything, I suppose I need to check into it to see exactly what I need. I'm told to get new springs, but...is that all: What's with this judder spring thing...should I swap them too? And here's my main question, which concerns how I drive this thing: I gather that the small squares of pad material on each friction plate is what keeps the clutch engaging/disengaging...am I to assume that when a clutch slips, those small pads have worn away, leaving that particular clutch plate smooth (or smoothER that it was when new)? I'm asking b/c I'm wondering if it is normal when a clutch starts to slip that it slips in only one gear like mine is doing in 2nd? I guess I have worry creeping in my mind that the dogs on 2nd gear are gone and I may have to undercut the tranny gears on yet another motorcycle on yet another 2nd gear. I've done this on another bike...kinda a PITA. It seems odd to me (and lends me to think the tranny might need to be undercut) that only 2nd gear slips. And now it seems to be slipping & bucking at a different RPM than before...then: 10k. now: 8k. Again, 1st and 3rd - 6th still pull solidly like a freight train, just 2nd has me a bit worried now.... your thoughts? Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted September 4, 2012 Share Posted September 4, 2012 Hmm, if the clutch was slipping, it should do it in all gears, not just second. Link to comment Share on other sites More sharing options...
Beck Posted September 4, 2012 Share Posted September 4, 2012 Slipping on second makes sense, especially if it happens when you are trying to redline the motor. I believe that 2nd gear forks and sychronizers tend to be the ones that wear out first on a bike's gearbox as second gear is where a lot of torque is typically used when accelerating a bike from slow speed or a stop. That kinda relates to clutches slipping most on 2nd gear then. Beck 95 VFR Link to comment Share on other sites More sharing options...
WGREGT Posted September 4, 2012 Author Share Posted September 4, 2012 Slipping on second makes sense, especially if it happens when you are trying to redline the motor. I believe that 2nd gear forks and sychronizers tend to be the ones that wear out first on a bike's gearbox as second gear is where a lot of torque is typically used when accelerating a bike from slow speed or a stop. That kinda relates to clutches slipping most on 2nd gear then. Beck 95 VFR So...you're thinking that if it's slipping most in 2nd, then the 2nd gear forks might be gone as well? Link to comment Share on other sites More sharing options...
Guest Posted September 4, 2012 Share Posted September 4, 2012 If your 2nd gear forks were gone it would make an unmistakably horrible sound when you hit the power. Link to comment Share on other sites More sharing options...
Member Contributer mk2davis Posted September 4, 2012 Member Contributer Share Posted September 4, 2012 If your as aggressive in gears 3-6 as you are in 2, then I would expect a failing clutch to slip more as you upshift and roll on throttle. It also seems like successfully shifting through all your gears without the clutch seems to indicate your tranny is not the problem. Not that I think I know what your problem is. If your gentle in 2nd but nail 3rd, what happens? Link to comment Share on other sites More sharing options...
GadiantonRob Posted September 4, 2012 Share Posted September 4, 2012 Mine had same issue. Replace clutch plates and get stiffer springs. Problem fixed. Link to comment Share on other sites More sharing options...
WGREGT Posted September 4, 2012 Author Share Posted September 4, 2012 If your gentle in 2nd but nail 3rd, what happens? Nothing but raw, unadulterated, earth-shaking, VFR power. Link to comment Share on other sites More sharing options...
WGREGT Posted September 4, 2012 Author Share Posted September 4, 2012 Mine had same issue. Replace clutch plates and get stiffer springs. Problem fixed. Same issue on the same bike? Cool. You went with the OEM schtuff for replacement? Link to comment Share on other sites More sharing options...
GadiantonRob Posted September 4, 2012 Share Posted September 4, 2012 Yup. That or Vesrah plates. Guy who did the work (knowledgeable fellow, I may add) said stay away from EBC, and that Vesrah made alot of OEM plates for the manufacturers. Only thing that was different were the stiffer springs I had installed, since I read somewhere that the Viffer's are a little soft and wear out, which is probably what your experiencing. Link to comment Share on other sites More sharing options...
samaki Posted September 4, 2012 Share Posted September 4, 2012 If your clutch was slipping it would do it in all gears and be even more noticeable in higher gears as the load on the clutch is greater due to the increased gear ratio. Sounds to me like you have worn engagement dogs on the second gearset. It is likely that under heavy loads the dogs are disengaging due to sloped engagement surfaces. Aggressive upshifts, particularly without the clutch, would cause this. Link to comment Share on other sites More sharing options...
WGREGT Posted September 5, 2012 Author Share Posted September 5, 2012 I've only upshifted/downshifted without the clutch 2x since I've had the bike, and that was last week to test out this whole theory. All of my other agressive upshifts (mostly) and aggressive downshifts (few) have been with the full use of the clutch. Link to comment Share on other sites More sharing options...
Beck Posted September 5, 2012 Share Posted September 5, 2012 Yup. That or Vesrah plates. Guy who did the work (knowledgeable fellow, I may add) said stay away from EBC, ....... I had bad experiences with EBC too, but with their brake pads which ruined (quickly glazed and deeply grooved) the front disc on my Hawk back in the 90's. Maybe their clutches are wonky too... Beck 95 VFR Link to comment Share on other sites More sharing options...
WGREGT Posted September 5, 2012 Author Share Posted September 5, 2012 I rode it home today from work and paid close attention to the shifting. 1st is still A-OK all the way to red line. 2nd is sometimes OK if I roll into it gently, and will stay OK longer if I ease it higher, but just by giving it gas and no clutch it went from about 8K all the way thru red line and to the rev limiter each time. 3rd was still fine and 4th - 6th were fine on the freeway @ speed, up to about 90 with no slip or issues. Link to comment Share on other sites More sharing options...
Member Contributer Burns Posted September 5, 2012 Member Contributer Share Posted September 5, 2012 mine shows small signs like that when cold.. . I'm guessing I've starting to glaze the plates a little... but if I'm cracking the side-cover, I'm just dropping new ones in at that point.. Link to comment Share on other sites More sharing options...
WGREGT Posted September 5, 2012 Author Share Posted September 5, 2012 I guess I was unclear about this. When I said it went from 8k thru redline to the rev limiter, it wasn't b/c the bike was moving faster. It was like I suddenly pulled in the clutch handle and rev'd it to the moon. Link to comment Share on other sites More sharing options...
WGREGT Posted September 7, 2012 Author Share Posted September 7, 2012 I was @ a honda dealer getting my tire swapped yesterday, and I asked a tech about my bike and the slipping, and he said "start to worry about the transmission." He said if a clutch starts to slip, it will slip in all gears and all RPMs. He also said the oil will have a burnt small to it. Mine does not. So now, I don't know what to think. I guess I should take the clutch pack out this weekend and see if anything looks out of the ordinary. Link to comment Share on other sites More sharing options...
Member Contributer gswanson Posted September 7, 2012 Member Contributer Share Posted September 7, 2012 I would be looking at the clutch first before worrying about the tranny. Both the mainshaft and countershaft are splined, which along with the gear dogs, would prevent an individual gear from slipping unless the splines and dogs were worn completely smooth. If a splined gear was turning on the splined shaft it should make one hell of a noise and vibration and, I think, happen at any RPM not just high in the rev zone. I am no transmission expert, so take what I say any way you want, but I would look at the simplest solution (new clutch plates and springs) first. Link to comment Share on other sites More sharing options...
samaki Posted September 7, 2012 Share Posted September 7, 2012 You will likely come out cheaper just replacing the engine with a used one. Full disassembly and repairs of this sort can get quite expensive. Link to comment Share on other sites More sharing options...
WGREGT Posted September 7, 2012 Author Share Posted September 7, 2012 I'd do the work myself. I haven't had a bike in a dealership for many years. Link to comment Share on other sites More sharing options...
WGREGT Posted September 9, 2012 Author Share Posted September 9, 2012 Took the clutch pack out today, and looked at all the discs. The steel ones were not blue or black anywhere on any side, and the fiber ones still had some of the pad material on each and every one of them. So....when the fiber ones are done, do they get completely smooth? I have the OEM service manual, but didn't see any reference to tell if any of the plates are within spec or not. Any of you guys know if this info exists? Everything looks good and clean in there. No obvious marks or scrapes or anything like that. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted September 9, 2012 Member Contributer Share Posted September 9, 2012 pm sent. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted September 9, 2012 Member Contributer Share Posted September 9, 2012 your mechanic is a moron. .. well.. not thinking it all through anyway.. when you get the bike rolling your bike now slips a little.. you may not notice it.. you shift to second.. which is a BIG difference in power transfer .. so you notice.. now your bike is moving.. and you dont notice it too much as you shift higher, because the bike is moving if it was your shift fork, it would drop out of gear.. and feel very sloppy until it got to that point. in anycase.. yes.. there is a minimum friction plate thickness. and NO its not wearing all the material off. yes it IS in the manual... ditto for the drive plates. i dont have a 5th gen manual but i know its in there.. Link to comment Share on other sites More sharing options...
WGREGT Posted September 9, 2012 Author Share Posted September 9, 2012 I found the service limit spec numbers.They are buried in the front of the manual. I measured mine, and even though the springs are not at the service limit, they are lower than when new. Same with the fiber plates. I put the steel plates on my glass kitchen table, and none are warped or show any bluing. I do have a slight corn row pattern on the edges of the clutch basket fingers. Just a small series of slight indentions. No metal in the oil...I have a magnetic bolt and it was clean. Link to comment Share on other sites More sharing options...
Member Contributer JETS Posted September 10, 2012 Member Contributer Share Posted September 10, 2012 Any chance it is an oil issue? Clutch lubrication Energy Conserving (EC) oil can cause wet clutches to slip Many motorcycles have a wet clutch, where the clutch plates are immersed in oil. Some oils make the friction plates in the clutch slippery so that the clutch does not engage properly when shifting gears, or the clutch slips when the engine exceeds a certain torquelevel. Some oils contain friction reducing chemicals. A properly specified motorcycle oil will still allow for the appropriate lubrication and cooling of a motorcycle clutch, whilst maintaining 100% of the drive to be transmitted by the clutch, even under arduous operating conditions. One element of the JASO-MA standard is a friction test designed to determine suitability for wet clutch usage.[2][1] An oil that meets JASO-MA is considered appropriate for wet clutch operations. Oils marketed as motorcycle-specific will carry the JASO-MA label. [edit]References ^ a b Motorcycle Four Cycle Gasoline Engine Oil (JASO T 903:2011) Application Manual. JASO Engine Oil Standards Implementation Panel. May 2011. ^ a b c d "All About Motor Oil." Mark Lawrence. California Scientific. April 24, 2011. Retrieved March 8, 2012. <http://motorcycleinfo.calsci.com/Oils1.html > Wikibooks has more on the topic of: Motorcycle oil Link to comment Share on other sites More sharing options...
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