Working the bugs out New(to me)'83 XVZ12t

[Yammer Dan]

Puc already answered this one. I'll wake up after while......

Edited July 23, 2016 by Yammer Dan

[snyper316]

Hey 40,, here is an online copy of the 1300cc manual that I just found that @yamagrl posted up - its a PDF file.

http://www.yamahaventure.nl/pdf/servicemanualxvz13tf.pdf

 

I tried to locate a file like that for our scoots but so far no luck.. Lets see if Yamagrl may be able to help us out here with locating one?

 

By the way,, if your inquiry in the manual has to do with basic engine/tranny - drive system I am thinking the 1300cc should do you - again,, lets see what that guru - Yamagrl thinks!!

 

Hey Cowpuc I beleive i have the pdf Manual for our bikes so how would one gain access

[yamagrl]

PDF manuals are great and all but I'm an old school kinda shade tree mechanic. I want a dogeared greasy book laying on the gas tank when I'm trying to unscrew the inscrutable.

 

I agree totally. I printed mine out. It takes about 250 sheets printed both sides, clamped between 2 pieces of wood and drilled holes for binders. I even bring the appropriate printed manual with me when I go on the road.

 

Some people just print the section they are working with at the time.

 

I'm not sure about a "Dogeared book" but Puc might be able to point out a "Lop eared" one !

 

Hey 40,, here is an online copy of the 1300cc manual that I just found that @yamagrl posted up - its a PDF file.

http://www.yamahaventure.nl/pdf/servicemanualxvz13tf.pdf

 

I tried to locate a file like that for our scoots but so far no luck.. Lets see if Yamagrl may be able to help us out here with locating one?

 

By the way,, if your inquiry in the manual has to do with basic engine/tranny - drive system I am thinking the 1300cc should do you - again,, lets see what that guru - Yamagrl thinks!!

 

 

Easy Peasy

 

That link I posted was from http://www.yamahaventure.nl/index.html It's a pretty nice site and the owners manuals are there, too. along with Dingy'g Diagrams. I think most of these are on our site in the "Read Only" section as well. They probably got some of this from our site.

 

Here is Mk1 http://www.yamahaventure.nl/xvz-1200.html

 

Here is Mk2 http://www.yamahaventure.nl/xvz-1300.html

 

Here is Second Gen http://www.yamahaventure.nl/xvz-13tf.html

 

​Heather

[yamagrl]

When you order valve cover gaskets order then for 1999 - 2016 bike. Same gasket but they added a lip to them that makes them easier to install.

 

I used the 2nd gen valve cover gaskets once and they were a little easier, but I didn't like the way they looked, so I immediately shaved off the excess, even the half moons... that was a bit tricky.

 

I always say that if you like what you end up with you'll forget about what it took to get there.

 

Heather

Edited July 24, 2016 by yamagrl
typo

[yamagrl]

The 1st gen manuals and also The Vmax manuals were on the cd that Dingy enclosed with my Ignitech TCI.

 

So if some one needs the Vmax manuals let me know.

 

Maybe, when I have time I'll upload them all to my webserver and post a link.

[luvmy40]

Synchronized the carbs today. They weren't really that bad. Both sides were tolerably close front to back but they were way out left to right. Now they're perfect. Well as perfect as can be without verifying the valve's are in spec.

 

Now I need to let it cool down enough to reset the idle to 1k with out burning the bejeezes out of my hand. I'd like to get the name of the engineer who designed the idle control knob!

[luvmy40]

Got the idle trimmed down to 1krpm+/- and took a short run(No tags yet) and it looks like the popping on decel is gone. Didn't get out of second gear so it's not a for sure yet but it sounds much better. The idle isn't as smooth as my in line fours but it's not erratic, just a bit staccato in comparison.

[luvmy40]

Doing some repair work on the plastics now. I'll tackle the fuse block next week. It's hotter than a two dollar pistol out there!

[luvmy40]

Got everything put back together and took a longer ride today. It's still not perfect. The hesitation is gone but it's still popping loudly when going from >4.5krpm to closed throttle.

 

I just need to bite the bullet and do the valves and clean the carbs. Not a big deal but still a PITA. I really should know better by now than to expect an '80s bike to be turn key road ready!

Edited July 27, 2016 by luvmy40

[gaj1917]

Got everything put back together and took a longer ride today. It's still not perfect. The hesitation is gone but it's still popping loudly when going from >4.5krpm to closed throttle.

 

I just need to bit the bullet and do the valves and clean the carbs. Not a big deal but still a PITA. I really should know better by now than to expect an '80 bike to be turn key road ready!

 

I think you'll find that valve adjustment will help. You may find the gap on some to be just about zero. Another thing to check are the carb diaphragm rubbers for pin holes or cracks, although a significant problem there should have shown up when syncing I would think.

[yamagrl]

I doubt the valve adjustment will effect the popping much but never-the-less they may very well need adjustment.

 

Even if you have holes in the slide diaphragms you would still likely get a decent sync. You would simply be compensating in your adjustment for the vacuum loss caused by the pin holes.

The popping may be caused by your idle mixture. Try enriching it a bit.

It may also be caused by the air cutoff/enrichment valve. That's the little diaphragm on on the side of each karb. Item 16.

 

​http://www.partzilla.com/parts/search/Yamaha/Motorcycle/1983/XVZ12TDK/CARBURETOR/parts.html

 

Here is an aftermarket from eBay but I do not have any experience with them. Remember each karb has one.

http://www.ebay.com/itm/K-S-Carburetor-Air-Cut-Off-Valves-for-Yamaha-XVZ1200T-Venture-83-84-87-88-/311652844530?hash=item488ff503f2:g:E1gAAOSwRQlXgGi6&vxp=mtr

 

Here's some from Sirius Consolidatedhttp://www.siriusconinc.com/pro-detail.php?pid=&product_id=1089

Many of us have ordered slide diaphragms from Sirius. I have them in Big Red. Use a guitar pick to install them http://www.siriusconinc.com/pro-detail.php?pid=&product_id=1794

 

[gaj1917]

Some exhaust popping is normal, but in my case it was very audible. My understanding is, as yamagrl points out, that popping is caused by a lean mixture that occurs upon decel, as air gets sucked into the cylinder or exhaust manifold mixing with unburnt fuel. In my case, where some of my valve clearances were close to zero, I reasoned that valves, exhaust in particular, were opening longer than normal, allowing more air then normal to be sucked into the cylinder or manifold. Anyway, once I adjusted valve clearances, I was back to normal popping. I'd be interested to see what happens in your case luvmy40.

[cowpuc]

Probably sound simplistic but most, if not all, of the back firing and exhaust popping I have experienced with the MK1's have been leaky exhaust gasket/cracks in collectors/rusty pin holes in muffs and stuff like that. Any spot that will allow air into the exhaust system so unburned fuel can ignite has the potential for causing issues of popping/backfiring IMHO..

I mentioned that crazy sounding idea to another member (think it was @T.J.) a while back as he was having similar issues with one of his scoots.. After playing around with the nausance for a while he tried regasketing his exhaust system and, if I recall correctly - it worked (even a Puc gets one right once in while ). Might be worth a quick check for air leaks in the exhaust system..

As far as cracked - disconnected or pin holed slide diaphrams,, I have had my fair share of those puppys happen and, again IMHO, those problems have usually shown up in lack of performance (the go grip loosing some of its go) and not usually associated with exhaust cackle - again, IMHO..

Speaking of "lean conditions", there is a little plastic box sitting right below the TCI that I, because the correct name slips my pea brain right now, will refer to as a vacuum balance box of sorts.. I have had to repair/replace/ work on a couple of those thru the years that, and this is a theory, have deformed and allowed air leaks because of riding in extremely high desert temps for hours and hours on end - sort of cooked the things if you will.. Air leaks there will cause some funky lean conditions and performance issues but, and relying on my somewhat challenged memory of days gone by, I dont recall even that being exhaust cackle related.. Might take a peek at the "seams" along that box too though.. @yamagrl,,,,,, what the heck is the proper name for the black plastic box of which I speak,,, I keep racking my brain and am getting a headache:doh:..

Messed up this thread enough,, onward to the next one

Puc

[yamagrl]

YICS Yamaha Induction Control System

[bongobobny]

Pucster, glad you chimed in about the exhaust gaskets, they do indeed cause popping on decel!

 

Yah, the YICS plastic box IS known for developing cracks, especially on the seams! Also the rubber hoses can, and do, deteriorate. The YICS is something that makes a difference in theory, but in reality does not seem to make a difference! Yamaha stopped using the system, now the vacuum ports are plugged off with caps that you remove to sync the carbs on the front carbs. Interesting note, a newbee GFRicky recently bought a 2nd gen, and we noticed someone had modd'ed the system and interconnected the vacuum ports on both sides with a tee adapter on the left and right sides, making it look somewhat like an attempt to "equalize" the carb vacuums sort of like what the YICS does...

[venturesome]

I relocated the YICS on mine... to a shelf in the shop! I can't tell the difference.

[luvmy40]

So, the YICS chamber on the XJ series is integral to the head. I just assumed these were similar. I kind of questioned doing a valve sync. without blocking the YICS ports. What I'm understanding from these comments is that the YICS chamber on the Ventures is a separate entity and connected via the intake vacuum nipples?

 

All the vac nips on mine were capped so the YICS is disabled. Is that a correct assumption?

[yamagrl]

The yics connections not the ones on the rubber carb boots. They are actually on the heads. They may have been capped off.

[luvmy40]

Ahh, I'll dig in a bit and get her figured out someday!

 

Fuse box is done and all the accessories are now fuse protected. The PO (or PPO?) had just wired the cig lighter and some other "Stuff"(unidentified as yet) directly to the battery.

[snyper316]

Ahh, I'll dig in a bit and get her figured out someday!

 

Fuse box is done and all the accessories are now fuse protected. The PO (or PPO?) had just wired the cig lighter and some other "Stuff"(unidentified as yet) directly to the battery.

 

Possible battery charge connector but if not that sounds scary.... have fun with that I had a car once that had well everything was hooked right up to the battery it was crazy....

[yamagrl]

The yics connections not the ones on the rubber carb boots. They are actually on the heads. They may have been capped off.

 

That is what you're looking for. That's #1 YICS connection. Number 4 is also easy to find. 2 and 3 are a bit harder to get to.

 

[luvmy40]

Thanks for the great pic and information yamagrl!

 

I stopped by my local Yam shop with the Venture today. Turns out the service manager is a Venture buff and was happy to see another '83 in good shape. He told me it was the smoothest running 3 cylinder venture he'd ever heard!

 

Turns out it is only hitting on 3 at idle and mid. WOT smooths out on all 4 so its a partially clogged jet or emulsion tube. He suggested running a couple tanks of gas with Engine Med additive before I tear the carbs out, so I picked up a few bottles as they are cheap.

 

The good news is it appears that the diaphragms are good. All four pistons spring back with a "suction delay"(?) I mean they don't just snap back quickly which would indicate a bad diaphragm. I'm saying this poorly! DoesyaknowwhatImean?

 

I also changed the plugs and checked the spark, all four look hot and steady. I didn't shock the bejeezes out of myself so the wires are pretty good too!

Edited July 27, 2016 by luvmy40

[yamagrl]

DoesyaknowwhatImean

 

​Yup!

[luvmy40]

To steal a phrase from the Warmernistas, "It's worse than we thought!"

 

Looks like she's only firing on 2(left side)cylinders at idle! I can pull either front or rear plug wire on the right side with no discernible effect on the idle. Pull one of the left wires and she dies.

 

At 4krpm, pulling the front right wire causes a stumble/hesitation. Pulling the right rear has no effect.

 

What are the coil and wire supposed to ohm out? All four had what looked to be strong spark but I'd feel better once I measure the coil/wire resistance.

 

I'll have to see if I have a 12mm adapter for my compression tester and check that as well. I did order a 12mm adapter for my Colortune today.

 

I will probably pull the carbs this weekend. Once more into the fray!

Edited July 29, 2016 by luvmy40
sp

[yamagrl]

To steal a phrase from the Warmernistas, "It's worse than we thought!"

 

What are the coil and wire supposed to ohm out? All four had what looked to be strong spark but I'd fell better once I measure the coil/wire resistance.

 

 

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