Driveshaft woes

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randu

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New to vmax, new to forums... decided to save some $ and remove rear tire to take to Cycle Gear to install new tire. Never messed w a driveshaft before but figured I was competent enough. Unfortunately, instead of the driveshaft separating at the final drive/ tire, the whole shaft came out. Got tire on, reinstalled and bolted everything back together. Thought I pulled it off til I tried to ride-horrible grinding noise. Didn’t ride, shut it off and took tire off again. Drive shaft will now not come out or go back in to where the splines seem to engage. The shaft is also sitting left of center in tubing and won’t go in straight. What to do??!- can I access the front splines of drive shaft somewhere? Is there a fix for this anyone knows about? Did I just ruin my new ( old) project bike? -help?
 
Nah, probably nothing wrong other than the splines aren't properly-engaged. Just remove the rear end w/the driveshaft attached, and try, try again. See that plug in the driveshaft housing by the engine? You can pop that out, and use that as a place to view your effort to insert the splines correctly.
 
I’m trying to understand why the driveshaft came out during a rear wheel removal.

Indeed a mystery, even with Dymags and wider tyre I only need to deflate it to get the wheel out.

Mr Randu, Can we assume that the splines are OK and not damaged?
If so this is how I get mine in (if I'm allowed to say that?).

First step is to make sure that the UJ is facing downwards; it may be easier to see this if you pull the rubber boot on the middle gear back.
Now make the the driveshaft also points down, you may need to rotate the shaft a little.

Sit on the floor behind the swinging arm and feed the assembly in and feel for the UJ. With a little jiggling about you should be able to get the two to engage and one final shove and it's in.

That's easy to type but it can be a right bitch. It either goes in strait away or it seems to take ages. Whilst I haven't tried this it may be possible to have an assistant guide it it from the UJ end if the fore, sorry rubber boot is pulled back.

Please not that any smutty innuendo or association with real life experiences about this post are in the readers mind. :eek: ;)
 
When removing the rear diff that will almost always pull the shaft with it due to the friction of the seal in the diff is greater then the friction of the shaft in the u-joint. Once the rear diff is out you will want to remove the shaft from the diff and reinstall it first. Then install the diff. Before snugging the diff down all the way you need to reinstall the wheel/tire/brake assembly to hold it all squared up then you can tighten the nuts on the diff to arm.
 
I can't visualise what is going on but before you drive off, put the bike on the centre stand and rotate the rear wheel to check all is ok before applying power. Then turn engine on, clutch in, put it in gear and slowly release clutch to check. That way you puts no stress on the drivetrain.

My guess, and hopefully I am wrong, is somehow the splined end was not fully seated and now has been chewed up so it won't come out, assuming it is even possible to assemble it like that.
 
thank you all and yes 02GF74, im afraid thats exactly what happened. it completely snugged all the way down but once all put together and put in gear (my biggest mistake) it made awful grinding sound. and the shaft refuses to come out again (it came out automatically when i first pulled the wheel) it also will not re-seat in tube in an apparent straight line, tried to re-engage it for hours and all it will do is come back out about an inch or so. im off tomorrow and will try to figure out how to see that end of shaft/spline behind rubber boot. Fire-Medic, can you explain the 'plug in the driveshaft housing near the engine'? its not the chrome circular on frame directly in front of driveshaft is it? thank you all again. i havent even ridden this bike yet aside from a test drive!, i finally got it legal, replace the tire, attempted to set off on my maiden voyage and -!@#$, hopefully its something i can figure out
 
thank you all and yes 02GF74, im afraid thats exactly what happened. it completely snugged all the way down but once all put together and put in gear (my biggest mistake) it made awful grinding sound. and the shaft refuses to come out again (it came out automatically when i first pulled the wheel) it also will not re-seat in tube in an apparent straight line, tried to re-engage it for hours and all it will do is come back out about an inch or so. im off tomorrow and will try to figure out how to see that end of shaft/spline behind rubber boot. Fire-Medic, can you explain the 'plug in the driveshaft housing near the engine'? its not the chrome circular on frame directly in front of driveshaft is it? thank you all again. i havent even ridden this bike yet aside from a test drive!, i finally got it legal, replace the tire, attempted to set off on my maiden voyage and -!@#$, hopefully its something i can figure out
No. Here's a pic.
VMax driveshaft rubber plug.jpg
 
With the driveshaft out, the "collar" the driveshaft fits into, will fall down. When Installing the driveshaft, tilt the driveshaft slightly up (to pick the collar up) and spin the driveshaft to the right. Thats the easiest way that Ive found to make it drop into place.
 
^^^ that sounds plausible, you'd think Yamaha would have designed it so that would not be possible. It may well be the UJ and shaft are wedged, if the shaft cannot be pulled out then maybe putting into gear and rolling backwards to reverse what was done can free it? Note. this is my best guess so don't blame me if something breaks!!
 
thanks for the help y'all. w these posts i figured out a way to look down the shaft housing and use a wire through top hole, to hold joint up to return splines/shaft to its proper place.
-i took a leap of faith w buying this bike (my first Max-friend of a friend kind of thing).spent the last month just trying to make it safe enough to ride. finally got ready (again) for first ride over 20mph, thought i was good to go, and then right off the rip:-it kicks out of gear in 2nd around 5000 rpm. -tranny rebuild? not that bad?- also, at around 55/60 mph bike completely loses exceleration and just kinda putters in and out. i know this could be alot of things, but the guy gave me a receipt for local shop carb rebuild from this past july. -so, clutch? compression issue? carbs sucking air?-any ideas? i really hate to give the nearby (not so great) shops more of my $!-thank you again!
 
Carbs left sitting with gas in 'em for 7 months, unfortunately probably need a cleaning of the pilot jets, the left one in the jet block. The orifice is tiny. It easily becomes plugged, and idle-low speed operation is affected. While you might think &*%$$@! small pilot jets are plugged-up is an evil way to extract $$ from your pocketbook, it's a fact of life in the use (or, perhaps non-use) of a VMax. I'd have to say that learning how-to tear-down a quartet of VMax carbs to the two-pair point, so you can remove the float bowls, and the jet block, for a thorough cleaning, is about as-important as learning that as you pass 6,000 rpm it's time for an E-ticket ride, and you don't want to be on sandy pavement, wet pavement, oil/ATF-covered pavement, you get the idea. I suggest buying four jet block gaskets before you open things up, and the needle valves for the floats. OEM is best here, though I've used the K&L needle valves with no problem, they're available separately, while you have to buy the OEM needle valves and seats as a set, which will cost you much-more. The guys on-here who rebuild carburetors as a business will say, "OEM parts only" and you're likely gonna have no issues going OEM. Read another member's issues with an aftermarket set of carburetor rebuild components, he sent 'em back.

Yes, you likely have a bad 2nd gear engagement dogs set. The male dogs are worn, the female holes into-which they engage are worn, and the easiest thing to do is to avoid use of 2nd gear, shift 1-to-3: skip 2nd gear. Engine removal, and splitting the cases is the only way to proceed here. Consider getting the gears undercut, it helps shifting, and while it costs $$$, while the transmission is apart is the time to do it. You might want to look for Damon's media on eBay motors. He has 'em for cleaning/rebuilding carburetors and yes, the engine, to-fix the 2nd gear 'no-work no-mo' problem.

I forget where you are, please consider adding your location below your screen name. Someone close-by may have a resource available to you.

Did you replace the gas filter? You can buy one for ~$7 from your local automotive parts shop, a generic sealed cartridge filter, or you can get one off ebay that is rebuildable, with a sintered bronze replaceable element. Russell I think had the design, there are ebay motors knock-offs, do a search on the forum, or just search eBay. If you get the throwaway, open your to-be-discarded cartridge, to examine what it's been catching.

Just from a point of information, shine a light into the gas tank, and what do you see on the sides/bottom? It should be shiny-clean. If a prior owner tried sealing it, and did a crappy job, you won't see that. There are various acid/alkaline ways to clean gas tanks, electrolysis, and mechanical methods like media blasting. Search on the forum for more info. If you have a rusty gas tank, it's useless to clean the carburetors, without fixing the gas tank, or replacing it, if it's got perforation.
 
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Wow-thank you so much for the info. I knew I was in for a whole new experience w 4 carbs ( single carbs or fuel injection only in the past)- I hadn’t gotten around to fuel filter but that’ll be next. If the tank looks clean would it be safe to run some sea foam or fuel cleaner first to see if it helps?( before taking carbs apart). Bought this as a project bike, just hope I get it to a riding state sooner than later. I’m a novice motorcycle mechanic at best. ( a little better w cars).- but I’ve already surprised myself w some of the stuff I’ve managed to fix , so I’m gonna keep on trying. Thanks again !
 
It's not gonna hurt anything but I doubt it will help.

Where do you live? Someone by you nay be able to help.
 

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