Jump to content
Sign in to follow this  

Suzuki RV90 smokes a lot!

Recommended Posts

I just aquired a 74 RV90. This chick magnet runs great buts smokes a lot. I've gone through and adjusted the oil pump to the recommended setting. Removed the old 2 stroke oil and put in fresh Belray. Even after it warms up it smokes a bunch. Black oil drips out of the tail pipe! It's embarrassing to ride as a I leave a trail of blue smoke down the street.

Any thoughts? Could it be a bad seal on the clutch side leaking from the clutch into the case?

I appreciate any help!

Share this post


Link to post
Share on other sites

if you are very concerned about it sucking in trans oil then put in a precise amout in the bike, ride it around then drain and check if their is any missing. BUt i would probably say your jetting is off, running rich. buy a 1size smaller pilot and the next 2-3sizes smaller main jets. you will also need to adjust your needle clip position too. when in doubt look up jetting FAQ on this site. good luck

Share this post


Link to post
Share on other sites

Thanks for the advice. I did monitor the amount of clutch fluid. I didn't change.

I've heard of people re jetting for various reasons. Why would this bike need to be re jetted? The original jet should be the correct jet to provide the right mixture, right? Or could have the jet worn?

Share this post


Link to post
Share on other sites

usually jetting is generic, not suitable for all climates and elevations. but you brought up a good point, the age would suggest their could be wear. or if this bike is new to you, the previous owner didnt care about the excess oil (spooge) coming out the exhaust.

no matter what, its worth taking the carb apart and looking at the jets and needle. but if its smoking a lot all threw the rpm range your jetting is probably off. the trick with a 2t is having it smoke some SOME, but you never want it to not smoke!

also what mixing ratio are you at? and what ratio did the previous owner run it at? if your running a richer mix of oil that would make it smoke more in the first place.

Share this post


Link to post
Share on other sites

Its a plug and play bike, don't touch the jetting providing its stock, but there are exceptions to that rule. Might be a worn topend or a dirty carb. 35Yrs can do alot to a bike so don't be surprised that alot of parts are worn.

Also Belray isn't a good choice of oil for that bike. I would find something cheap and readily available where the chemical composition hasn't changed over the years like Spectro or even non synthetics like Pennzoil, Wolveshead or any basic generic nonsynthetic premix oil.

Share this post


Link to post
Share on other sites

It's an oil injected motor. I'm not sure what the motor runs. I could look it up. I set the injector pump at the recommended amount based on the manual. Carb is clean and rebuilt. I never checked the jet for wear but the bike only has 2000 original miles.

Oh yeah, the compression (cold) is 130lbs. Is it possible to bypass the injector pump and run mixed gas to determine if it's the injector pump? I think there are lines going into the crankcase in addition to the carb. I don't want to starve the lower end for this experiment. Thanks for everyones feedback!

Share this post


Link to post
Share on other sites
It's an oil injected motor. I'm not sure what the motor runs. I could look it up. I set the injector pump at the recommended amount based on the manual. Carb is clean and rebuilt. I never checked the jet for wear but the bike only has 2000 original miles.

Oh yeah, the compression (cold) is 130lbs. Is it possible to bypass the injector pump and run mixed gas to determine if it's the injector pump? I think there are lines going into the crankcase in addition to the carb. I don't want to starve the lower end for this experiment. Thanks for everyones feedback!

I would bet that if you put Suzuki CCI 2 stroke oil in there it would run perfect. It has happened with snowmobiles, guys go out and buy new sleds and then go buy a high dollar injector oil only to find out that they burn 2 qts in 60 miles. My buddy did that and was pissed about burning all that oil until he talked to a sled machanic and told him that the injectors only handle certain viscosity oils and the best bet is to use the dealer oil.

I wouldn't close off the pump. They never go bad.

Share this post


Link to post
Share on other sites

I haven't swapped the oil out yet but I did drain the clutch oil then start it up (but not ride around). If clutch oil was leaking past the seal into the case, the smoking should stop. It didn't. Still smoked. I'll try putting some old school oil in.

Share this post


Link to post
Share on other sites

I don't think its the seal, but if you ask my wife she'll tell you I'm wrong all the time.

You can do a leakdown test. The build link is in the Suzuki FAQs page.

If the test works out then I would find the cheap oil, drain the oil tank and refill and run the piss out of it and see if it clears up. Might be residual from the bike sitting or storage lube etc etc.

Share this post


Link to post
Share on other sites

i saw a polaris 90 2t that sat around for years and all the oil had drained into the head. in addition to what mihylo said, you might want to take the spark plug out and kick the engine over a few times. see if any excess oil comes out the plug hole.

just a thought, but it will tell you if your oil injector is working over time.

Share this post


Link to post
Share on other sites

also check your spark plugs clean them if it is burning a exess of oil then those spark plugs must be getting gummed up as for your smoking problem try adjusting the oil pump so that it gets a little less oil and experiment with that

Share this post


Link to post
Share on other sites

also how about your valves, rings, and piston

my friend sunk his fourwheeler and a few days later his 4 stroke suzuki eigar smoked like a 2 stroke he changed his piston rings and it ran like a champ

Share this post


Link to post
Share on other sites
also how about your valves, rings, and piston

my friend sunk his fourwheeler and a few days later his 4 stroke suzuki eigar smoked like a 2 stroke he changed his piston rings and it ran like a champ

no valves in a 2 stroke. but yes if the top end was getting old it would run richer...but it being an oil injected bike would not make it run richer on oil.

your buddies 4 stroke smoked because it was sucking in engine oil from the crank case. he has already eliminated this problem.

tell you friend to change his oil asap after it sinks, and not to let off the throttle when in the water!

Share this post


Link to post
Share on other sites

My rv90 smoked like crazy when I used premix in the oil tank after I bought the bike. I switched to oil made for the autolube pumps and now it only smokes when it's cold.

Could there be something in there that is preventing the oil pump valve from fully closing?

2006_pd1015032_1.jpg

Notice the oil weight?

Here's some more oil pump literature

http://www.thumpertalk.com/forum/archive/index.php/t-791147.html

http://www.dansmc.com/2_stroke_oilpump.htm

Share this post


Link to post
Share on other sites

Hi I live near Brisbane in Queensland Australia .Ihave rv90 1974 model and i am having trouble getting an oil comparable the sae20 recommended. Ihave tried a modern bike oil that is suitagle for injection systems but seems too thin and smokes too much.Is the original still available?. Any suggestions. Cheers

Share this post


Link to post
Share on other sites

hi     I am using castrol activ 2t seems to work alright. I still have trouble with bogging down with acceleration. I am adjusting the float level to specs but when i lean the bike over to the left about 60 degrees it stops. Any sugestions. bike not rideable.

Share this post


Link to post
Share on other sites

I suppose to end this thread I will reveal the true culprit The choke lever is to be pushed away to turn it off!!!!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...