1st gen carbs

[dgc67]

I was reading an old review of a V45 from Cycle World and it stated that the front carbs on a V45 are downdrafts and the rear ones are sidedrafts.  Anyone ever hear this?  If this is true I am wondering what impact it would have if you got them mixed around accidentally.

[Slydynbye]

I have heard that, It would be BAD to mix them up.

[dgc67]

Interesting.  I am going to have to look real hard at the ones I have at home.  The person before me had taken the carbs off for sure, he said so, and the bike had no top end power at all.  I cleaned them to no avail, so bought some of ebay, cleaned those and it runs great.  I wonder if he might have gotten them mixed up.  You would have to pull the shafts/butterflys to do it though.

[Greg Cothern]

The front and rear carbs on the vintage Magna's are slightly different.  They have different rated springs, jets etc... 

Its due to the rear carbs facing more forward in the airbox and air flow is different...  The Supers are also like this...

[Chad in Michigan]

It's not just those either. i've looked up some of the differences between the 3rd gen magna and the same year vfr750. the vfr uses a different crank, i think it is a 360 degree, or is that the magna.. i forget. and the cams are gear driven, not chain driven. but as for the carbs, the front two are different from the back. the fronts had bigger main jets by one size and a different needle than the rear two carbs.. i wonder why our carbs aren't like that? they also use way bigger mains than we use. i think the carbs are similar in design, but the air intake is slighly larger. i think we have a 34mm carb and the vfr is 36mm but i don't remember. i di remember looking at the parts list on one of the parts lookup places and comparing what makes them different from ours.

[Greg Cothern]

Our 3rd gen Magna carbs are not like that cause they straightened the forward lean of the engine to upright.  Thus the 4 carb trumpets are now equal inside the airbox..

Back to the main question here, keep the front carb components separate from the rear carb components, they HAVE to go back into their correct homes.... 

If you get them mixed up you will have out of balanced air fuel mixtures.  One set being too lean and the other set being too rich.

[GroceryGetter]

  Great... I know that is what EXaCTLY the other guy did....   he told me he cleaned them all in a big bucket and put them together...Jeez, and I thought replacing the intake boots would solve the running issue.....  I am NO super TECH carb man by any means, what is a good way to do this?  or should I take the carbs to my local mechanic?

[roboto65]

Well if you have the manual it will give you a base line on which carb body has what something like 1&3s and 4&2s have different jets and shorter springs the VFs and Magnas share the same engines and carbs pretty much!!