| Author | Message | ||
     Ontheroad68 |
Got the new top-end in, new front wheel bearings, brake pads and front rotor and getting some break-in miles on the bike. Everything is going well except that the belt has slipped a tooth on me while riding a few times. It always happens in a lower gear under heavy acceleration. I removed the rear wheel and checked the belt, sprockets and tensioner. Everything appears to be in good condition and lined up well. Re-installed rear wheel by the method listed in the shop manual. The belt is snug but doesn't appear to be real tight, not sure how tight it is supposed to be. The bike had 40K (hard) miles, the belt has aprox. 20K. I can spend $100 on a new tensioner but not sure that would do it. Thoughts? | ||
| Ourdee |
Look in the teeth of the rear sprocket/pulley. Is all the coating worn off? | ||
| Ontheroad68 |
Some of the coating is wearing on the top of the teeth. The manual says any more than 1/4" of coating wear and change the sprocket. I really don't see the tensioner being the problem so perhaps it is the rear sprocket? Has anyone else had this problem? | ||
| Tootal |
The belt should be near banjo tight. If it's got quite of bit of play then check the transmission output shaft bearing. You would probably have noticed this already, just throwing it out there since I've seen this before. | ||
| Ontheroad68 |
That sounds bad. | ||
| Ontheroad68 |
The bike rides great so I'm pretty sure I'd know if the trans bearing was bad, but I'll pull the wheel/belt off this week and have a look. | ||
| Pushr0d |
There's the rear bearings, too. If the right side has failed, it may give no other symptom other than the wheel (and sprocket) aren't true. Is the belt tracking on the rear sprocket properly? DAMHIKT. | ||
| Griffmeister |
Don’t want to be the bearer of bad news but that could very well be the transmission. Has nothing to do with bearings, excess wear on the forks, gears and dogs causes what is called ratcheting. Feels just like the belt jumping a tooth. Happened to me in third gear. I could simulate it at a standstill and you might be able to also. Have a helper watch your belt for confirmation, hold the brakes on and apply power in each gear starting in first and shifting up. Mine was okay in first and second but when I hit third it started skipping. Having a helper confirmed that the belt was rock steady. Of course as others have said, make sure that the belt is in good condition first. | ||
| Ontheroad68 |
Unfortunately this sounds like the likely cause. My drivetrain is in good condition and I really can't see a way for the belt to skip. I also know the previous owner rode the bike hard and sold it to me really cheap, saying it needed a top-end rebuild (it didn't). I'll try this out when it stops pouring rain. Thanks a bunch for the tip, you may have just saved me a lot of $$ and frustration. | ||
| Ontheroad68 |
Could not get the bike to jump at a stand still but did get it to jump a couple time while riding today and it always happened in 3rd gear. It doesn't happen very often but this will need addressing. Did you split the cases to find out what went bad? | ||
| Tpehak |
If the problem is in transmission it will be cheaper and faster to buy and install new motor than fixing the existing one. It will be probably cheaper to buy whole new motorcycle. (Message edited by TPEHAK on February 02, 2020) | ||
| Ontheroad68 |
I've rebuilt a few (6?) engines and transmissions over the years and am trying to figure out which parts in the transmission have gone bad to cause this. It would certainly be faster to drop a new engine in it but not cheaper if I rebuild the transmission myself. I'm very familiar with motorcycle transmissions and can not figure out what has gone bad to cause this. | ||
| Firemanjim |
If the dogs that engage the gears wear it can jump out momentarily under a load. hayabusa notorious for second gear like that. If you are mechanically incline it is just labor to dissassemble the engine. Need some gaskets and time. | ||
| Ontheroad68 |
Ok, the dogs are wearing, I can buy that. The shift forks no. I just put a fresh top end on the bike and really don't feel like doing a complete disassembly, but I'd probably rather do that than spend $1k on an Ebay motor. We'll see. and thanks for the tip! | ||
| Ontheroad68 |
I probably won't do anything real soon, it doesn't jump very often and I'm having a great time riding the bike on the few dry days we get around here. | ||
| Tpehak |
It is not just time and gaskets. You will need also a bunch of special expensive tools and replacements for bad parts. Some of those tools like big presses require space. So you also need a shop. (Message edited by TPEHAK on February 03, 2020) | ||
| Griffmeister |
That’s what sucks, third gear is the fun gear, just the right amount of engine braking and acceleration for all the nice backroads. I can pretty much guarantee that you will need to replace the shift fork, the sliding dog and third gear. The total cost in parts for that is not as bad as you might think but the rest of the parts for an engine rebuild can add quite a bit to that total. Normally, after a shift, the dogs carry all of the load. If the tranny is skipping what it is doing is disengaging the dogs. The only thing that is keeping the dogs engaged is the fork which is now under a load that it was not designed to take. The fact that they are able to disengage means that there is already excess wear on the fork and the groove in the sliding dog. Even with all that work, if you just want to swap out bad parts you could probably complete the job at less than a grand. I went the extra mile and sent my transmission to R & D Motorsports. They magnafluxed all the parts and shot peened them then remachined the dogs to put a slight taper on the contact surface that would actually pull the dog into the gear to keep it engaged under load. The only downside is that this added over $800 to the cost of repair, so just consider that an option. Special tools, yes and no. You do need typical rebuilding tools and make friends with someone that has an arbor press. The case half needs to be supported in a funky way to press the transmission back in, but you can make something with good measurement. Half of a door hinge can be ground to fit between the primary gears to lock them in place. A real big help would be to make something that holds the output sprocket, this is a must for loosening and torquing the shaft nut. A little fabricating skill and you’ll be good. | ||
| Tpehak |
If you will decide to do this make sure you take pictures and post them here. Many people stated they dis this work but nobody shared the process. | ||
| Smorris |
Might verify correct tensioner on bike. Don't think wrong belt would even fit. IIRC there are 2 or 3 dots on the tensioner for the "long" bikes | ||
| Ontheroad68 |
I'm still not sure weather I will rebuild or buy a used engine. I have inquired about several on ebay but the sellers admit there is no way to verify the mileage. The instrument cluster is "missing" and they "heard" the bike had XXX miles. More than one seller says this. The only verifiable engine has 32K on it. Anyhow, If I decide to go through the engine I can post some pics, but I normally just go step by step from the maintenance manual, and anyone can do that. I'll keep you posted, But I'm still riding it to work several days a week and it's still fun! | ||
| Arry |
OTR68-- On Craigs List, Portland OR, motorcycle parts, there is a listing for a Buell XB transmission (innards). It would be a big job, but you say you've had experience with such. Good Luck | ||
| Ontheroad68 |
I saw the 2007 trans parts on CL and am considering them since they only have 16K. But I heard Buell (and Harley) made a couple of small improvements to the 2008+ transmissions. The size of the shafts that the shift forks ride on for example. This is not yet confirmed, I'll need to do some research. But thanks for the heads up. | ||
| Ontheroad68 |
My original plan for the transmission was to just change third gear and the dog that it rides on since the rest of the transmission is fine. We'll see. | ||
| Firemanjim |
Make sure you get compatible parts as XB transmissions have gone through several iterations. | ||
| Steveford |
Considering the amount of work involved in getting the guts out I would think you'd bite the bullet and buy new parts. We had to split the cases at the Buell XB Technical Training up in Milwaukee but that was easy as they already had the motor out for us. | ||
| Shoggin |
But getting the motor out is the easy part.  You have a great point. Why lament $20-50-100 difference in parts on a whole weekend of labor. Wanna do it all again? I wouldn't want to... (Message edited by shoggin on February 08, 2020) | ||
| Steveford |
It's a bit of a project, all right. | ||
| Ontheroad68 |
I am now officially unemployed so I have some time to do the transmission. My right arm is bad and I am working through some other health issues so I will probably try to do an hour a day, more if I'm up for it. I just spent a month in the hospital and nearly died from Covid 19 + Pneumonia. BIG THANKS to Griffmeister who clued me in to the possibility of the transmission being the problem (I later confirmed this), and for the tips for the lower end. I am amazed and glad that there is such community support for a motorcycle that has been out of production for 10 years. I'll post some pics along the way but this will not be a quick build. | ||
| Griffmeister |
A+ for ambition but please don’t hurt yourself in the process. Probably a good idea to have an extra supply of straps and blocks to add support where needed. Don’t forget to take lots of pictures. Not for our entertainment (unless it’s Facebook worthy), but just for the reassembly. Really helps when you wonder where that part went or how was that wire routed? Hope your recovery progresses well. | ||
| Ontheroad68 |
Got the motor out and apart and the only issue I could find was noticeable wear on one of the shift forks and the dog it rides on. Replaced said parts and put back together. Hope it works! QUESTION: I am putting motor back together and it appears that the although the rocker boxes are the same part # front and rear, once the rocker arms are installed (I never took them out) they become front/rear. I didn't mark them when I took them out. See the problem? How can I identify the front or rear? I have actually already installed them (today) then I realized they are directional. Please help! | ||
| Ontheroad68 |
Or am I misinterpreting the parts catalog, and they are both the same once assembled? If the ratios of the front/rear are the same it should work either way, right? I'm thinking this is more likely now that I have studied the IPC more closely. (Message edited by ontheroad68 on May 30, 2020) | ||
| Bobbuell1961 |
While it is always good to put a part back in it's original place thy are the same part. | ||
| Tootal |
If they are all the same length then it won't matter. If not then check endplay and arrange them to have the least amount of endplay greater than .003". |
