What gas mileage do you get ?

[greg_in_london]

Okay, I'll give them a ring and report on the results. It will probably be a couple of days before I manage it, though.

 

[update Wednesday]

I spoke to the UK shop today. They mentioned some bikes that they have information for, including XJ550, XZ550 and XV535, but not the XVZ1200. They said that if I could take parts out and find numbers on them, then they could order parts, but that Yamaha (and the other Jap manufacturers) will not tell them what parts are inside the carburettors and son they can't look them up.

 

Squeeze - have you bought any parts for the Venture from Topham ? Do they have more information in the German company or did you have to tell them the part number stamped on the part ? Did you keep a note of the parts ?

 

I've ordered some cheap V-Max float needles from Ebay in the hope that they will fit, but really want the right emulsion tubes and needle. Does anyone have a reference for these for an '83 bike or one apart that you could check for a part number ??? Pretty please.

Edited May 21, 2008 by greg_in_london

[greg_in_london]

Well I've just had confirmation those needle valves are in the post and will be with me for the middle of next week (fingers crossed) so I suppose I should get the carbs taken off in readiness. That way I may be able to get the part numbers and order some emulsion tubes before the end of the week.. That might be pushing my luck, though.

 

It would be good if I could as we're going camping for the weekend on the Friday.

 

After next week, there won't be much time to get ready before the Summer trip and I really need some improved mpg. 30mpg (25mpg [uS]) on a three and a half thousand mile tour will hurt - even if we don't get stranded between petrol stations.

[Squeeze]

...

Squeeze - have you bought any parts for the Venture from Topham ? Do they have more information in the German company or did you have to tell them the part number stamped on the part ? Did you keep a note of the parts ?

 

I've ordered some cheap V-Max float needles from Ebay in the hope that they will fit, but really want the right emulsion tubes and needle. Does anyone have a reference for these for an '83 bike or one apart that you could check for a part number ??? Pretty please.

 

Greg, i'm sorry, but you're edited Postings didn't came up last night using the 'new Posts' Button.

 

No, i haven't ordered Parts for the Venture Carbs, so, i don't know if Topham has Informations at Hand. The Vmax Floater Needles will fit your Carbs, don't worry about that. I don't know about the any Numbers on the Emulsion Tubes, i haven't noticed any. The Jets have Numbers on them, that's sure. But you could take all Informations out of the 1Gen Manual, there is a good Listing of Parts in use in the Specs Section of the Manual.

[greg_in_london]

Well the parts listed in the manual are 5FX59-1 for the needle and Y-0 for the needle jet. (that's for the L model, but I think the DL is the same) I had presumed that they were Yamaha designation, rather than Mikuni references, but I may have been a plonker and able to order the parts all along.... (I did search for them on the Mikuni site though and had no hits).

 

I'll ring tomorow and find out.

 

Looking at the TK specs, that uses 5GLZ37 and a X-6 needle. The numbers are so different I wonder just how similar they are. Mine has the smaller main and pilot jets - you'd expect it to be an economical model, so I wonder which carb specs people have that get good mileage - if the parts were cheaper I could experiment.

 

[i edited the post because I thought that repeat postings can seem to be there just to push a topic to the top of the list - if something is an edit rather than a new bit of info it seems politer to do that - but maybe I was a little reticent in this case.]

[GigaWhiskey]

Soooooo, what is the record number of posts for a thread on this site?

 

Well, this one ain't it, sorry. It is the Great VR Scavenger Hunt with 312 replies and 11, 634 views.

 

Y'all got some work to do!!!!

 

Sorry for intruding on your thread!

Edited May 22, 2008 by GigaWhiskey

[Squeeze]

Well the parts listed in the manual are 5FX59-1 for the needle and Y-0 for the needle jet. (that's for the L model, but I think the DL is the same) I had presumed that they were Yamaha designation, rather than Mikuni references, but I may have been a plonker and able to order the parts all along.... (I did search for them on the Mikuni site though and had no hits).

 

I'll ring tomorow and find out.

 

Looking at the TK specs, that uses 5GLZ37 and a X-6 needle. The numbers are so different I wonder just how similar they are. Mine has the smaller main and pilot jets - you'd expect it to be an economical model, so I wonder which carb specs people have that get good mileage - if the parts were cheaper I could experiment.

 

[i edited the post because I thought that repeat postings can seem to be there just to push a topic to the top of the list - if something is an edit rather than a new bit of info it seems politer to do that - but maybe I was a little reticent in this case.]

 

Greg,

 

these Numbers sound familiar to me. Topham will know them and I think you will have a good Outcome of your Call.

 

But, please remember, these CV Carbs are a System, you just can't get in there and change Jets to smaller Sizes and expect to lower the Mileage. The Jet Needle has 5 or 6 Sections, the 5GLZ37 stands for 6 Sections in Diameters and Angles on the Needle. There are over 6000 different Needles.

[greg_in_london]

No - I'll stick with the stock figure for now, but if it were to turn out that those models that get good mileage/mpg have carb specification and those of us with poorer figures, then this could be an area worth investigating. Well eventually, maybe.

 

If a carb refurb yields good results, though, then obviously I'll be happy.

 

Soooooo, what is the record number of posts for a thread on this site?

 

Well, this one ain't it, sorry. It is the Great VR Scavenger Hunt with 312 replies and 11, 634 views.

Well we're a long way from solving the fuel economy problem yet, so maybe this thread has a few more posts left in it.

[greg_in_london]

Aaaaagh

 

I missed Alan's Performance yesterday (they close at 4:30pm) and they're closed today (Saturday) and won't open again until Tuesday because of the bank holiday...which will probably mess up my chances of doing it all this week.

 

I rang the helpful guy at www.motocarb.co.uk again. He said that the codes in the manual are mikuni designations, but without the initial three digit series code are useless. essentially the series code give the external size, the figure in the manual the hole in the middle that supplies air/fuel. I asked if it would be possible to use the code from another model if we knew that series number (ie XV535 - one that I think kits are available for) but as the numbers are not stmped on the jet/needle there's no way to be sure. He also said again that neither these series codes nor the individual parts are listed in their catalogues due to an agreement with Yamaha not to supply them.

 

I've got a friend who runs a Yamaha shop who I haven't visited for ages, so this may be the time to do it and just bite the bullet as to the price. Otherwise I won't know until mid week whether Alan's Performance can even supply the bits. Otherwise an email to Topham may be better than me struggling with my spoken German. It always seems easier for people to say 'no' when you email, though..

Model	Venture XVZ12TK	XVZ12TDK (has CLASS)	Venture Royale XVZ12 L or DL	Venture Royale XVZ12 KC2 or DKC2
frame no.	JYA26H00*xxxxxx	JYA31M00*DAxxxxxx	(L) JYA41R00*EAxxxxxx (DL) JYA41V00*EAxxxxxx	(KC2)JYA47R00*DAxxxxxx (DKC2) JYA47T00*DAxxxxxx
Yam carb ID	26H 00	26H 00	41R00
main jet	#117.5	#117.5
main air jet	#65	#65	#55
jet needle needle jet	5GLZ37 X-6	5GLZ18-3 X-6	5FX59-1 Y-0
pilot air jet	no.1 #80 no.2 #180	#80	#80 #180
pilot outlet	0.8
pilot jet	#42.5	#42.5	#37.5
pilot outlet	0.8
bypass	B.P.1 0.8 B.P.2 0.8 B.P.3 0.9
valve seat size	1.5
starter jet	G.S.1 #45 G.S.2 #0.8
fuel level	14~0.5mm	16.5-17.5 mm	15.5-16.5 mm
Mikuni ref ?	BDS34	BDS34	BDS34	BDS34
carb diameter ?	??	??	??
mileage ??	Do people with this model get good mpg ?	Do people with this model get good mpg ?	I get low 30's mpg (UK) with this model solo, 30 mpg (25mpgUS). Do otherpeople with this model get good mpg ?	Do people with this model get good mpg ?
other comment	I don't know how many of these were made.	Manual lists only one pilot air jet. Changed float level.	Were the changes to make the cruise control work ?	The manual gives the code number, but no further information - I have presumed the L/DL info applies.

 

I have no idea if we've been comparing like with like when talking about mileage/mpg figures. I also don't know how many later models there were -it took long enough to enter this lot (sorry about the big gap btw - I don't know why it is there nor how to remove it)

I understand that at some point the carb body diameter may have been changed, but whether they are interchangeable (ie the same carb rubbers fit) I also can't say.

 

If my jetting was altered to make cruise control, though (and all other cruise control riders get worse mpg than non-L/DL models) then it might be worth trying to switch carbs or do a re-jet - but surely someone else must have made this change in the past ???

 

What does everyone else think ?

Meanwhile I think I need to ring my friend in the Yamaha shop - except he won't be able to order anything now until Tuesday doh:

Edited June 1, 2008 by greg_in_london

[greg_in_london]

I've just found the Alan's Performance site : it was Allen's Performance http://www.allensperformance.co.uk/ and I located the table below. Maybe they will be able to help after all - at least it has some 3 digit code numbers. Unless these are the codes they have not agreed to keep secret. I think TM and VM are their slide carb applications, not CV carb. The parts might be the same if we know the codes, though..

Series	Part Number	Size	Application
110	VM13/21-size	E-6 to F-6	VM16-353
145	VM15H1/17-size	N-6 to O-6	VM17-8101 / VM18-144 / VM20-151
159	VM34/05-size	N-0 to R-0	VM30-83 / VM32-193 / VM32-33 / VM34-168 / VM34-275 / VM36-4
166	VM34/17-size	O-8 to R-8	VM38-9
175	VM30/46-size	O-8 to Q-2	VM28-418
182	VM28/86-size	O-2 to P-8	VM26-8637 / VM26-8639
224	VM44/10-size	AA-0 to CC-5	VM40-4 / VM44-3
239	VM22/294-size	N-2 to P-2	VM20-179 / VM20-273
249	VM22/313-size	N-8 to P-8	VM24-473
295	VM13/151-size	E-6 to F-0	VM13-83
325	VM14/233-size	E-4 to E-8	VM14-8340
332	VM26/581-size	N-4 to P-4	VM24-489 / VM26-606
389	785-24001-size	O-0 to R-8	TM32-1 / TM34-2 / TM36-2 / TM38-85 / TM38-86
426	784-31002-size	D-0 to E-2	VM20-327
454	784-21005-size	O-0 to q-8	TM24-9
512	784-24008-size	P-0 to Q-0	TM28-1
568	784-13002-size	P-0 to P-8 / Y-0 to Z-2	RS / TM36-31 / TM40-6
622	784-232401-size	N-4 to 0-6	TM27-8006 / TM30-8006
633	784-13005-size	Q-0 to T-0	TM38-131 / TM38-157 / TMX38-1 / TMX38-5
640	784-24111-size	P-2 to Q-2	TM33-12
680	785-40004-size	O-8 to P-8	TMR/TDMR
681	784-31030-size	D-0 to E-8	VM16-438
723	784-430000-size	Y-4 to Y-8	TM42-6 / TM45-2 /TM48-2

[greg_in_london]

This is getting even worse. My mate's not answering the phone so he's probably having a liquid lunch atthe hostelry opposite his shop.

 

In the meantime I thought I'd look up the yamaha part numbers om the microfiches for the XVZ12TDK, the XVZ12L and the XVZ12DL (courtesy www.yamahaventureclub.co.uk )

 

I get:

model...........needle set........................... main nozzle (aka needle jet)

XVZ12TDK.... 26H-1490J-00-00 .................26H-14941-06-00

XVZ12L ........26H-1490J-00-00 .................26H-14941-06-00

XVZ12DL ......26H-1490J-00-00 .................26H-14941-06-00

 

and the same for the DLKC2 model. I'll let someone else check the rest on the list.

 

What gives, though. The original manual spec says that they had different settings, but the microfiches say they're all the same.

Was there a recall and some carburettors reset (for the better or the worse ?) Was this applied to all markets? If anyone orders from Yamaha they'll get the same bits regardless of model. Was this because of continuous improvements or to meet emissions (ie possbly worse performance/economy)

 

It does suggest to me that Yamaha messed about a bit with the jetting and it could be pot luck which specification people actually got. The question is, how do we work out which is the optimum ?

[greg_in_london]

Now I don't want to seem obsessed by this, but ........

According to the microfiche I'm looking at for the XVZ12DL http://www.yamahaventureclub.co.uk/downloads/XVZ12DL.PDF on pages 15 & 16, the main air jet is 80, not 65 as stated in the manual - surely this would make the carbs run richer at low throttle openings. Additionally the pilot air jet is given as 170 in the fiche rather than 180 as stated in the manual.

 

Hmmm - checking again, the L model microfiche has the same specs as the manual - maybe the manual supplemement for L, DL, KC2 and DKC2 rather unhelpfully left out the specifications/data for the last three of those.

 

It doesn't help my confidence that the #65/#80 discrepancy can be explained by Yamaha mistaking the main air jet for the pilot air jets (and thereby leaving the real main air jets off the fiches altogether).

 

I'm going to tear into it on Monday to be ready to do the float nedles when they arrive. I'll just have to see what I can get on the other parts and hope for the best, unless anyone has any inspiration, or a spare set of carbs that had been getting good mpg.

[funrider]

Most bikes but especially my 86 VRs mileage is determined by speed..Of course things like head winds and climbing hills are major factors but overall speed is the main factor..I usually get about 40 mpg as long as I keep the speed to 65mph or less and take off gently from stops..I live in Nevada which has a lot of open roads so I find myself going 80-90 quite frequently..then my mileage slips to 33-35 mpg..

 

 

 

my bike is a 87 VR and I get about the same, depends on how I ride.

[greg_in_london]

So Funrider you get 40 mpg US (about 45mpg UK) at 65mph and slip to 33-5mpg US (38-40mpg UK) at 80-90 mph.

 

Some others are getting no more than 40mpg (UK) at 50-55mph and 30mpg (UK - 25mpg US) at speeds of 70-80mph.

 

These bikes are in most cases sensitive to speed, but also to something else - the question is exactly what. It doesn't seem to be timing, so maybe it's carburation. Do you know exatly which model you have, or the engine number ?

[greg_in_london]

I suspect that I'm losing people's attention with the detail here, but for the record, while I've got my carbs apart I'm going to post the details of what I'm finding inside.

 

Butterfly valve has 140 stamped on each disc.

 

Needle is 5FX59

Needle jet is 438 Y-0 (90% sure it says 438 - don't know if that's the 'series' or not) [Y-0 jet diameter is 3.1mm, X-6 is 3.08mm]

main bleed pipe is 9A

main jet is 117.5 There is also a letter which could be H

the jet block has 25 stamped on it

pilot mixture jet is 37.5

pilot air jets are 80 and 170.

 

I'll add more information as I keep pulling them apart (time to eat, now).

 

I haven't taken the float needle valve seat out yet. On the microfiche it looks as if it should come out 'backwards' - ie through the carb body, but I can only see that it could be a push fit from the inside, with maybe an o-ring for interference. The manual doesn't say - can anyone say if is just a case of wiggling with a pair of pliers and pulling it out ?

Edited May 29, 2008 by greg_in_london

[Gearhead]

Greg, I haven't had these apart, but I've never seen a carb where the seat didn't unscrew from inside the bowl.

 

Jeremy

[greg_in_london]

Hi Gearhead - I've got some new ones coming (hopefully tomorrow) and if they've got a thread fine http://i3.ebayimg.com/02/i/000/b1/85/fbdf_2.JPGbut from the picture I can't see one. The seller said they were for a V-max but I'm told they're the same. If the needles arthe same and I can't get the housing out then I'll just use the new needle. They will either fit or they won't - they weren't too expensive - they were off Ebay.

Edited May 28, 2008 by greg_in_london

[greg_in_london]

I spoke to Andy at http://www.nrp-carbs.co.uk who unfortunately can't provide the nozzles at the moment, other than by ordering via Yamaha. He was of the view that the needles and nozzles/needle jets do not wear significantly on Ventures or V-Maxes and that is usually the soft bits - diaphragms, seals and o-rings that go first. Obviously some other people have been given different advice.

 

My VR has just under 55,000 on the clock (the last twenty five-thirty with a sidecar attached). So far I've taken one of the cabs apart - I'd rather not risk mixing bits up and the float needles haven't arrived yet - and I can't see wear on the nozzle/needle jet. I'm going to sort out some magnification, but it doesn't look oval to my eyes. When I block the end, blow through the hole on the side and slide needle in and out, air flows fairly freely only with the needle most of the way out, with flow reducing as the needle is pushed in, until almost no air passes with the needle al the way in.

I wondered if there should be an air tight seal, but then possibly the needle would stick/jam ?

I have never changed this part on a motorcycle before - had not considered that it would wear, except I was told that it could be a problem on these carbs. Now I really don't know, but don't want to pay Yamaha prices and don't have confidence that Yamaha are honest about their parts when I don't know for sure what the best specification is, nor whether I would get it if I ordered it !

 

Andy also checked the jet sizes for me - the Y-0 (DL model) is dia 3.10mm, the X-6 (TDK) is dia 3.08mm. That's not a big difference, but might have an impact on mileage/fuel consumption.

 

We still need a lot more information, folks, and I suspect that it might be useful if people could check which model they have (ie by the engine/chassis number) as well as saying what they get to the gallon. Then I suppose I'd have to take on the task of collating the information and seeing if there's a link.

[Gearhead]

Greg, FYI I'm still following your link. I admire your tenacity with this. I can supply the numbers from my 87, but not right now.

 

I wouldn't say the needles and jets wear out a lot, but I've seen it on other bikes. On my Virago I could tell visually, as well as two other ways. One, I took the biggest drill bit that would fit in the jet and it would rock in the hole farther in one direction than in the other. Two, I could use my 6" caliper and actually fit the ends of the ID measuring tangs in the jet and measure bigger in one direction than the other. On the Venture, I haven't taken them out. When I replaced the slides I shone a bright flashlight down to the emulsion tubes and looked carefully. They looked round after 55k miles.

 

I've wondered about wear on the needles and how to detect it. I've always just inspected them, looking at the ramped sides for wear and never found any obvious wear.

 

Here's another variable. The Virago, which wore out the tubes, has had a Dynojet kit in it for quite some time. DJ needles are stainless, factory needles are aluminum.

 

I wouldn't expect the needle to totally close off the emulsion tube.

 

As for that needle seat in the pic, it sure doesn't seem to be threaded. That's new to me! FWIW, I've never replaced MC needles or seats. They've never worn out in any obvious way. I figure as long as the carb maintains a consistent fuel level then they are working.

 

Jeremy

[capn eddie]

My 87 VR gets 40 to 44 miles per gal. if i stay around 65 mph, last week while riding with my friend and his girl friend (who just started riding) at 55 to 60 mph i got 48 mpg. But when riding with the VTX riders at speeds of 80 to 90 mph i get around 30 to 36 mpg. :confused24:It all depends on how much you twist the gas. Just can't seem to let them get past me with out twisting the gas.

[greg_in_london]

Hi Gearhead, no I've never changed the float needles before either, but I don't seem to get consistent results checking the float height and now I've got one carb flooding, so buying replacements seemed a way of eliminating one problem. If they don't arrive by tomorrow, I may have to put them back together, but with the float height set lower. I had been setting it to about 14mm as per the TDK, but for my model should be 16mm, which will give a bigger safety margin. That will be closer to how it was set before, when it was running better anyway.

 

Esaffley, I'm not sure how many different models I have specs for, but could you let me know which model you have - I don't know if there was only one specification available in 1987. It seems likely, but in 1983-4 there were at least four !

What you get a 80-90 is as good or better than I ever got with conservative riding. What you get with slow riding some people probably don't even believe, so if we could check what your jetting is, or anything else that is different on your model, it could be useful for the rest of us.

[greg_in_london]

Hmmm - something I would have ordered if I'd known. Around the nozzle/needle jet there is an o-ring which is probably well worth changing. I've got plenty of o-rings, but these are unhelpfully narrow. If you did this make sure that you have four o-rings, inside diameter 8mm (or 7mm would do) by 1mm thick.

I haven't got those, so I am trying to make do with 3.5 mm by 2mm thick, stretched over the jet, on the basis that when stretched to (more than) twice its diameter it will have the right cross section. If it works I'll say so, if not I'll have to tear them apart again and locate some skinny o-rings. Grrrr.

Edited May 29, 2008 by greg_in_london

[Gearhead]

Greg, as for the o-rings, make sure you are using some that are fuel resistant. Buna-N (nitrile) are typically used for oil applications, like inside the engine, but I'm not sure if they're suitable for fuel. Hardware-store o-rings are definitely NOT suitable, in my experience. They are for water.

 

I had in inconsistently flooding carb on my Virago. It wasn't the needle and seat, but the float! I don't know how the plastic floats are constructed - are they hollow or solid? Anyway, mine was either leaking or absorbing fuel and was heavy. When I took them both out and floated them in a cup of gasoline, the heavy one barely floated, distinctly different from the other one. I once read a post from a guy who said you could bake the floats dry again, then coat them with model airplane dope which is totally fuel-proof.

 

Jeremy

[mbrood]

I guess I'm looking mainly at the 1st gen bikes (know little about 2nd gen).

One thing i haven't seen addressed... or just missed it...

 

Has anyone with a good mileage bike measured the control voltage going from the boost sensor to the TCI (@ 1,000 rpm idle) and then compare that to some of the lower mileage bikes? If the timing is off due to an error from the boost sensor, couldn't that hold a major change in mileage bike to bike?

 

And why the heck can't we find a Mazda or Toyota replecement for that stupidly expensive part?

[greg_in_london]

Hi Gearhead - all the floats float quite happily in petrol, so I don't think any have gone porous.

 

I'm being ultra careful checking all the float levels while still on the bench. I'm finding that a level to the top of the float (measured to the middle of the float - not the highest point) from the central needle jet part of the casting of 20.5mm gives a fuel level of about 17mm, whereas a height of 20mm is giving a float level of about 16mm. I'm measiring the level from the bottom of the meniscus (the bottom of the curve in the tube). I do find it difficult to measure the fuel/float level accurately, though.

 

As a rule of thumb, this had the top of the float pretty much horizontal (tip from yamahaventureclub) on the first I did, but on the second the angle was slightly higher to get the right height. Don't know why - the pivot pin didn't look bent.

 

mbrood - no I don't think that has been mentioned. Are you aware of it being an issue? It is quite some time since I looked at the timing, but when I did it was within the correct range. With the vacuum advance it was hard to know exactly what position/mark the fully advanced ignition would show at, though.

If this was a factor with age, though, we would expect more bikes to have their mileage/consumption drop over time, which does not seem to be the case.

[capn eddie]

Greg my bike is a XVZ13DS ID# JYA1NL007, i don't know jet sizes, what ever is stock for this year. Just had carbs adjusted and synchronization done about three months ago by donelson cycles . Also had valves set at same time. I do the sea foam thing about every two months. Bike only has 33000 miles on it , bought it in sept. 07 with 26000 on it and everything was working on it. Sorry i don't have more info for you but i haven't had to do much to it. I did gut the collector and put jardine pipes on it , other than that it's stock. Just remembered k&n air filter also.

 

 

Ed.