New (to me) 85 Shadow VT700 ?'s (Updated)

[mydog8em]

Hi all, I just got my hands on an '85 700 a few weeks ago. The bike belonged to my wife's uncle who bought her brand new in early 86 I believe. When he 1st got her he rode a decent amount putting 18,200 miles on her and then parked her in late 90 only starting her here and there to warm up and taking her on short rides, he says he put on roughly 500 miles since 90 until now. Well he decided to sell and the wife and I told him we were interested so outta the kindness of his heart he gave her to us. Now hes my favorite uncle (in-law) anyway, the bike is nearly immaculate. The factory seat is perfect, never been laid down, all cables, hoses, chrome, etc are well above average, the pipes dont even have that 'burnt' coloration to them. some minor surface rust on the handlebars but I plan on taking care of that soon and all electrics and gages work fine. With her sitting as long as she has of course I drained, flushed and filled every fluid and filter on the bike, rode 10-20mi and did it again. I also changed the plugs. At 1st the bike was sluggish and grumpy but after a couple cans of sea foam thats been remedied. Now she has wonderful acceleration up to highway speeds but my problem is (and I'm not sure if this is normal or not for this bike) once she hits 70-75ish MPH she dont wanna go any faster. While she was running sluggish, 50-60 was her top speed and I was actually riding when whatever it was broke free and I felt the power increase immediately. For a minute I thot the throttle was sticking. But now, there've been times I was cruising 65-75ish on the highway and wanted to pass someone but she just didnt have it. I literally have to be on a down-hill to hit 80 on her but once shes there she'll stay at it (I dont make a habit of speeding on a bike but I would like to know her limitations). She starts right up, runs really well and does not seem to be sputtering, misfiring or bogging down at all even at highway speeds, no ticks, tocks, pings or clicks that I can hear and as far as I know shes all stock, no mods, etc. and with my big 290lb. @$$ on her she still gets 50-53mpg (est. 38-45 while she was still sluggish). I just wanted to know if maybe this is normal and if theres anything else I mite need to do (I know a carb cleaning mite be in order but I'm too skeered to do it myself and dont have the $ to do it right now, but soon as i can i will). A friend of mine I work with said that even tho shes a 2-cyl. with 4 plugs, one of the plugs mite not be firing correctly and I mite not even notice this on a normal ride and that this could be causing her not to get to a faster speed. Is there an easy way to tell if shes firing on all 4 plugs or would this even cause the speed problem (if it is a problem)? Or could it even be that I'm 290lbs.? lol. Thanks a ton for any info provided.

[sdanville]

I had that bike.
Running correctly its plenty fast. I weigh 250.
you have tarnished carbs.
Run a few tanks of gas through it with carb cleaner.
Sea foam, or marvel mystery oil for example.
MAYBE you can get away with no rebuild.
A rebuild is just courage.

[MotoPsycho]

Unless something changed between '85 and '86, that bike should pull you past 100 easily.

I agree, check them carbs.

[Maraxion]

Originally Posted by '86VT700

Unless something changed between '85 and '86, that bike should pull you past 100 easily.

I agree, check them carbs.

The 85 Is a bit more powerfull, but basicly the same engine.

[mydog8em]

Thanks all for the replies, I kinda figgered it would be carb probs. I'll take care of it soon as I can. Thanks again.

[landon]

I have an 84 VT700C, I gunned it once to pass an RV and was doing 100mph before I even realized it, so yours should too.

[Maraxion]

Its hard to say the mas speed on them, but on the 5. gear(not overdrive) iv done 110 with load, id guess 120 or a bit more Is possible.
But then again, its not bikes that should go fast, but I need to follow my Girl friends Ducati

[mydog8em]

What're you running on the tach when you're 70-80ish? 70mph is exactly 4K and 80 was pushing 5K for me. I'm mid-way thru a 2nd tank of SeaFoam and she seems to be perking up more and more everyday. Haven't been on the freeway recently tho, only 45-55mph back roads.

[nbt racing]

I would suggest pulling (or having it done) those carbs and giving them a proper cleaning and inspection. We have seen countless cases like this and although we use sea foam on occasion and do believe it works to a degree, it is not the cure all. As i'm sure you know when bikes sit for a long period of time with fuel in them the potential for corosion and build up in the internal carb components is high. What your experiencing sounds like a partial blockage in the jets or a partially stuck throttle slide. The sea foam is gradually cleaning the passages in the jets but as you can imagine it is causing your bike to run lean which over time could lead to more expensive engine problems. Those are great bikes and I would hate to see you have any serious problems later on down the road.

[jonkun227]

Maybe you've already done it, but I have to agree with the above comments. Seafoam is okay at cleaning up partially blocked lines and jets, but neither it nor any other chemical known to man can (safely) unplug completely blocked jets. The chemical has to flow through it to do any good and it can't flow through it if it's completely blocked.

If you take it apart you'll find the main jets completely plugged up. You're running on your lower jets and they don't have enough flow to get you going any faster.

I bought my 85 after it sat for 8 or 9 years. I rode it for a week around town before I had time to clean out the carbs. After I did the first time I took it out around the neighborhood to try it out I flicked the throttle the way I had grown accustomed to and nearly fell off the back of the bike. If it hadn't been for the raised rear seat I'm sure I would have. I wasn't prepared for how much power it has.

The early Shadows and Magnas are sometimes called "Couch Rockets" because they're comfortable but FAST. Even the late 80s versions can't compete because they got heavy and sluggish.

One more story: The first time I took it on the freeway after I cleaned up the carbs I was running without a speedometer. I had accidentally broken the speedo cable while working on the front wheel. My wife was following me to our destination. I thought I was going about 80 mph. When we got there she was bright red and fuming. Apparently she had to go 90-95 just to keep me in sight.

This was about 2 weeks after I told her I was going to buy a tame motorcycle, "not one of those crotch rockets".

I love this bike.


- Jon