New and could use advise

[nova72]

Hi, my name is Ben and I just picked up a 1987 Yamaha Radian last week. It has 25k miles on it. This is my first bike and pretty new into the whole world of two wheels. It seems to run pretty well, but the owner told me that she was getting about 30mpg. That seems pretty low to me. i thought these should get mid 40's easy. am i wrong? I take it changing the plugs and wires, along with a new air filter would help a lot, but would it make that much of a difference? while poking around i found the air filter and looked oily & pretty dirty. these aren't oiled filters are they? i would guess the filter is a big part of it. and another thing i noticed was that the little rubber things that are between the head and the carbs is splitting a little, are those the things i have listed on the link below? and if so how hard is it to take them off, put them back on and get the bike started again. sorry about all of the questions, but ya never learn if you don't ask. I am trying to get as much knowledge as possible and do anything i can myself the correct way. Because i know that bike work is expensive.

thanks a bunch

Ben

http://item.express.ebay.com/YAMAHA-YX600-...cmdZExpressItem

[iomrob]

hi ben, welcome.

ok,first, i have not owned one of those, but it look a standard 4

no the air filter will not be oiled ,i take it when you said "it", its a standard filter in an airbox {where the filter is housed}

if its dirty change it, as it will cause poor running and fuel consumption.

as for the 30mpg, depends how you ride it, i for one have never bothered working out what any off my bikes get.

the items on the link {the pictured did not load} going by the name are the correct items. there are a few names for them , depending where you are in the world. inlet manifolds, inlet manifold rubbers, card mountings, inlet rubbers.

get them changed if they are splitting, if a split goes right through it will cause that pot to draw more air , which will makes it run weak, and can cause the cylinder to blow up. and this will happen 100 miles from home not 100 yards.

just change the lot for safety.

as for changing them , depends how you are at mechanical work, if you ok, they are quite easy to do . the main problem use to be they were held on with allen bolts {uk name for them} and were prone to rounding the allen slot and it was always the hardest one to get to that done it. {although that model could be bolts i dont know}.

if you fit the new ones correct ie, flush to the cylinder head {run the mounting bolts up evenly , not tighten one right up then fit the other} refit the carbs , some times heating the mountings with an hair dryer before fitting the carbs is a good idea as the rubber is quite hard, just warm them to make the rubber more softer, all four at once then fit the carbs quiclly before it cools down.

then refit the air box. i have found this part the hardest in the past {in fact once after 2 hours of trying, the air box got ripped out , thrown in the corner and a set of K'N's fitted.} as it seems with some air boxs , years of heat from the engine warps the air box.

if the card mountings, the carbs, and air box are all fitted on correctly, the bike will start no problem just a few extra turns on the starter. just make sure you leave one of the lock nuts on the cables to the carbs in place so the cables are at the same place as they come off.

if you have any worries , just buy a workshop manual for the model. but its not a hard job for someone with mechanical knowledge

hope this helps, someone on here could have more knowledge of these models. but as i said it looks a straight forward 4 cylinder

Rob

oh if you have trouble with the air box and go for 4 single filters fitted to the carbs, the carbs will need up jetted.