VM carbs vs. BS carbs / Nick, please read - nonpolitical LOL

[frosty5011]

Can anyone tell me if I can replace the older VM carbs with the newer BS carbs without any problems?

Looks like I might also get myself a '79 GS850G. This model, of course, still has the old VM carbs. I happen to have an extra set of carbs (32mm) from my '80 GS850GL which I'd like to put on the bike (if I get it) since the owner of the above bike stated that carbs all gummed up, out of adjustment, etc.

Since I pretty much know the BS carbs....having stipped and cleaned them numerous times....I would prefer to put them on if it presents no major problem. I assume both have 32mm throats.....since both were for the 850 cyl. head....or does the '79 model have different carb boots (which take different size carbs)? Only difficulty I can think of off hand might be the choke and throttle cable hookups....that these might be different.

What say the experts?

[Anonymous]

Re: VM carbs vs. BS carbs / Nick, please read - nonpolitical

I assume both have 32mm throats.....since both were for the 850 cyl. head....or does the '79 model have different carb boots (which take different size carbs)? Only difficulty I can think of off hand might be the choke and throttle cable hookups....that these might be different.

Seems to me someone mentioned a while back that the VM carbs have considerably smaller throats -- the BS carbs have the butterfly valve sitting in there, so the throat is bigger for a comparable carb.

I think the same poster said that the carbs were not interchangeable, because of this difference.

Michael

[earlfor]

Re: VM carbs vs. BS carbs / Nick, please read - nonpolitical

The 79 model with the VM carbs will have different size intakes, and different intake mount design. The VM and CV's are not interchangable.
You could put a set of CV''s on an early model, but you would have to replace the cylinder head with one that has the later style, larger diameter intakes.

Earl


[quote="frosty5011"]
I assume both have 32mm throats.....since both were for the 850 cyl. head....or does the '79 model have different carb boots (which take different size carbs)? Only difficulty I can think of off hand might be the choke and throttle cable hookups....that these might be different.

[Anonymous]

Earl is correct. I had a 79 GS850G for a while, and wanted to install the CV carbs off my old 82. No way. Won't fit.

The solution is obviously to get a head meant for a 1980 or more recent. I do have such a head available. If interested, let me know.

Nick

[frosty5011]

OK,

so the head is actually machined differently, and has different carb boots on it. Thanks, I didn't know that......didn't think Suzuki would've changed heads on GS850 from 79 to 80. Appreciate the info....if I do end up getting the bike and have problems with the old carbs on it....I might be coming back at you Nick.

Oh, and by the way Nick......what do you think of the current Iraq situation right now, should we....................

( Sorry, couldn't resist)

[Anonymous]

Iraq is what I do every time I play pool...

Iran is what I used to do to catch the bus every morning...

[shaftzuki]

A wise man once said "It's springtime, let's ride!!!" 8)

[Jay B]

Wasnt 79 the last year of the 750 overbored to 850 and 80 the first year the 850 was its own motor? That might explain all the dofferences.

[Anonymous]

Wasnt 79 the last year of the 750 overbored to 850 and 80 the first year the 850 was its own motor? That might explain all the dofferences.

Not really. The 850 was never just an overbored 750.

The 1980 model year (T models) was when the 1000 and 850 both changed to CV carbs as part of an upgrade, the heads needed to change to match.

[focus frenzy]

Wasnt 79 the last year of the 750 overbored to 850 and 80 the first year the 850 was its own motor? That might explain all the dofferences.

the 850 was based on the 750 design and does share the same stroke but the cylinders, head and crank cases are differant.

the chainge to cv style carbs for 1980 was the biggest change done to the 850, there were some minor updates done over the years of production, but basicly the engine remained the same.
suzuki changed the heads to use cv carbs on almost all of the GS's for 1980.

[Anonymous]

Changes from 79 GS850 to 80 GS850, besides the carbs:

1. Larger stator (12 coils to 18).
2. No kickstarter.
3. Different front master cylinder and calipers.
4. Slotted brake rotors front and rear. I've never noticed any difference in performance from slotted to solid.
4. Electronic ignition. 79 had points (yuck!)

Everything else is the same or interchangeable. Did I miss something? If so, tell me.

Nick