nickon's banshee repair / rebuild

[nickon]

Hi guys,

 

Belgian new guy reporting in on the forums Been reading up alot and there's some good info and helpful people on here! I've been an ATV enthusiast for a long time now, but never had the cash and opportunity to actually buy one. Now that I finished building my own house, I was finally able to snag an old, I think bone stock, Yamaha Banshee (pics below).

 

 

   

 

Let's get this out now, I'm new to wrenching! I hope you guys wanna me help out when I'm in need of some guidance I already ordered and received my copy of a Clymer manual and a Yamaha Banshee service manual to get me going. Credit to BansheeHQ already on those pointers!

 

I actually already brought it to the shop for some quick checkup. I have the feeling they didn't do much to it actually... Except for billing me... But yea I guess that's what you get when you don't know what you're talking about. Anyhow, what they told me they did was:

1. replaced the spark plugs
2. cleaned the carbs (supossedly)
   I can see some new tubing on the right carburator only and the left one is still leaking fuel as before...
3. fiddled with the carbs (supossedly)
   It wasn't and still isn't really starting from the first couple of kicks when cold...When it finally starts and I don't keep on the gas a bit, it doesn't idle but just dies. I think when I drive it for a while and the engine is hot, it does idle but I need to double check to be sure, haven't had alot of time to ride it lately.
4. broke drill bit on the rear brake caliper
   Rear brake pads were completely gone and they told me the rear brake caliper was not operating as it should. So they tried taking it of, breaking a drill bit on it, which is still in... How will I know if I'm able to still revise the caliper or if I need a new one?
5. checked the bearings
   They checked the bearings and told me the "front wheel bearings" and "rear axle bearings" have alot of wiggle and need to be replaced. Because this banshee is quite old and I feel like it didn't really get the servicing it deserved, it might be a good idea to just replace all bearings on it. How do I check if the bearings are any good still? And which bearings (front and back) should I def check?

Eventually it's my goal to fully rebuild this Banshee. But let's start small. Give this bike a thorough cleaning, fix the brake, the starting/leaking/idling issue and bearings so that I have a realiable and smooth(er) running Banshee I can take down the road

 

Probably more questions to come....

 

Thanks already!

Edited April 18, 2017 by nickon

[Profilact]

You are on the right track.  Do all of the bearings, dont forget about seals as well.  If you can post pics of the rear caliper and the carb issues you have we can better help you and advise on a repair or replace approach.

 

Buy a good compression tester and test compression as well.  It doesnt look like your motor has ever been apart but it wouldn't hurt to do a leakdown test.  Search this forum for all of the info you need.  Its here.

 

Welcome aboard.  Prepare to surrender your wallet!

[nickon]

Haha thanks. I'll get back on that.

 

I received my Bosch CP7827 compression tester earlier this week. Been planning on doing a compression test again. I've done one before but with a compression tester without a valve on the tube itself. That didn't really work out all that well :-D

 

Verstuurd vanaf mijn Nexus 5 met Tapatalk

[Canadianshee]

Congrates, if you can try and set a budget and stick with. They guys on here are a wealth of knowledge.

If you plan on getting into to motor at all , inspect everything before buying. You may come across something that needs done, that you may have not known. Happened to me had to replace clutch.

Have fun working on these is addicting.

 

Sent from my LG-H831 using Tapatalk

[nickon]

Did a clean (or should I say the first clean ever) of the banshee. Damn was she dirty. There's still some grease/dirt left in places I couldn't reach entirely, but she looks alot cleaner already. Anyhow, lots of surface rust on things, but didn't notice anything particularly broken or bent or anything at first sight besides the stuff I will mention below.

 

First off, I did a compression test on both of the cylinders, this is left and right respectively as you can see, both at about 115 psi. I'm at 125 feet (38m) above sea level and the motor should be all stock. Compression is not really as high as it should be I guess? But I'll let you guys judge and give advice on that.

 

 

 

For the back brake, I managed to get the broken wrench bit out of it after dismounting it from the bike (see first pic). It seemed to be quite loose in there from the start but it was still quite stuck and tricky to get out with a pair of pliers because I couldn't grip the broken bit firmly enough. The thread which had the broken bit inside it seems pretty worn out. Took some pictures to show you guys the overall state the break caliper is in. Would I be able to salvage and revise it or would you advise me to buy a new break caliper?

 

  

 

While inspecting the back break a bit further, I noticed a different part above the rear brake lever that seemed to be looser than it should be or might even be broken? That is, the plastic(?) part that is touching my finger. What is it exactly and what is it's purpose?

 

 

Now for some laughs and giggles. I disconnected the radiator hose from the clutch cover because I was worried that I introduced some water in that hose after spraying my radiator (from a distance) with my pressure washer. Boy, was there some fluid in there (obviously). I disconnected the hose only for a brief moment (not even a second I guess) and a gulp of coolant leaked out of it... Of course a banshee is liquid cooled but yea mistakes were made  Am I safe as long as the coolant reservoir near the back of my seat is still topped of? That's the same cooling circuit, right? Because I noticed there's also a cap on the radiator itself that can be unscrewed. Is there a need to 'bleed' the cooling system after such a mistake or is there no risk involved in possibly introducing some air bubbles?

 

As I rinsed off alot of dirt but also grease on the bearings, I should probably regrease all the joints? Also for replacing some of the bearings, I was wondering if aftermarket A-arms come with bearings included or not? And are they the same as stock bearings? Just a matter of judging whether it's worth it or not to replacing the bearings if I plan to upgrade the A-arms soon.

[nickon]

Stripped the back brake, everything seems intact and fine after it will be cleaned. The parking break was pretty rusty though... Cleaned it using WD-40 and compressed air without disassembling it. I didn't find any instructions in Clymer and didn't see a clear way to dismantle it?

 

 

 

The brake caliper bracket is still on as you can see in the picture above. The bolt thread is completly ruined... Any thoughts on how to fix that without buying a new bolt / bracket? I could also just leave it and clean the caliper with the bracket still on. But there is a rubber seal in there along with the bolt, so the break cleaner probably won't do it any good... What's the use of that seal any way?

 

 

 

Also, any thoughts on the compression test and the spilled coolant?

 

 

[nickon]

Rebuilt the back brake, but slightly damaged the rubber that is sealing the piston from the handbrake, so it started leaking there when bleeding the brakes  Anyone knows if I can get the seals seperately at a fair price (shipping to Belgium)? If not, I'm probably ordering a rear brake rebuild kit or going for a new (yfz / r700) caliper immediately.

So, 34°C over here this weekend, got my license plate and the bike insurrance ready and took her down the road for the very first time. It was fun while it lasted, but it seems to me like one of the pistons blew up after just a couple hours of riding... Suddenly the engine started shaking and the throttle response just dropped. Putting down the throttle doesn't rev the engine anymore and it sounds like only one piston is 'knocking' the engine properly. See the video below.

Two questions

1. How to determine what's wrong? I guess start by doing a compression test on both cylinders and see what I get out of that.
2. What could be the cause of this and is there any way I could have prevented it?

Thanks,
nickon

Edited May 29, 2017 by nickon

[Schweet97Z]

Start simple and work your way through the list. Figure out what cylinder isn't firing. Check spark. Make sure it's getting fuel. Make sure plug isn't fouled. Report back


Sent from my iPhone using Tapatalk

[nickon]

Thanks for the pointers Schweetz, I took my Clymer and started troubleshooting.  What I checked already:

SPARK

• Don't seem particularly fouled I guess? (see pic below), cleaned them nevertheless.
• Pulled out both spark plugs, grounded them against the cylinder and kickstarted the bike. Both give a nice blue spark. They're brand new.

COMPRESSION

• Did a compression test. Same compression tester, some pressure level on both cylinders as the test I did a couple weeks ago. (see pics below, left and right cyl respectively)

 

FUEL

• Old fuel from when I bought the bike was still in the tank. It was down to reserve level when the shit hit the fan. Wondering if this is a coincidence or not? Anyhow, drained the tank and put in freshly mixed fuel.
• Checked the venting tube on the fuel tank. It's open.
• Pulled of the fuel line, both run fuel nicely to the carbs.
• Left carburator is leaking fuel from the overflow tubing. This was already the case before. How can I check / make sure that both cylinders are getting fuel without pulling off the carbs? I know fuel is reaching the carburators from the test above.

PARKING BREAK CONTACT

• The Clymer mentioned the electric handbrake contact would limit the rpm of the engine. Perfect explanation I figured, because I pulled off my back- and parking brake for a revision and it still isn't on yet. Unfortunately this is not the problem. Just fired up the bike and purposely played with the parking brake contact while driving. When I break contact, the engine rpm is limited even further. When the contact is closed again, the engine revs 'freely' to a point where it stalls at a later point like before. The engine feels quite shaky and it isn't really delivering throttle smoothly, more like chugging / bouncing along...

Any advice you guys can give me that would point me in the right direction is appreciated.

Thanks,
nickon

[kawa110]

Unplug the tors brain.

Small Black box left side of bike

[Schweet97Z]

The plugs look wet but rightfully so if it's not running right. What is your jetting and are your carbs synchronized? Run through your carbs. Clean them set your float height and sync them. Why the FMF stickers on there? Did the bike previously have aftermarket pipes on but wasn't jetted accordingly for factory pipes?


Sent from my iPhone using Tapatalk

[nickon]

8 hours ago, kawa110 said:

Unplug the tors brain.

Small Black box left side of bike

Pulled it this morning and took the bike out for a minute, didn't do the trick...

4 hours ago, Schweet97Z said:

The plugs look wet but rightfully so if it's not running right. What is your jetting and are your carbs synchronized? Run through your carbs. Clean them set your float height and sync them. Why the FMF stickers on there? Did the bike previously have aftermarket pipes on but wasn't jetted accordingly for factory pipes?

When I bought the bike, I brought it to the dealer which told me he cleaned and synchronized them. If he actually did is another question (as he didn't really seem that trustworthy to me afterwards), so I don't know for sure.

Also no clue what my current jetting is, how do I get that information? (I'll read up on carbs...) As far as the FMF stickers go I don't know the answer either. It had a bunch of stickers on them and when I bought it, it was completely stock. I have no information on the seller selling parts seperately.

Do you think some carburator hickup can cause this kind of behavior midway down a ride? Anyway, never a lost cause to clean the carbs. As you mentioned the plugs look wet and I do sometimes have trouble kickstarting it so.

[bigweav81]

Have you checked your carb slides?

Sent from my SM-S820L using Tapatalk

[Schweet97Z]

Buy a carb sync tool it's a must have for any banshee owner. Take the bowls off the carbs and unscrew the main jet and pilot jet. Look at the numbers on them and report back. Carb issues can def cause it to act this way. In fact had a similar issue with my 04 when I got it. Jetted properly and synced carbs. Boom ran like a champ. Also go on YouTube and look for South Texas Banshee. He has a lot of step by step videos that will be very helpful to you. But definitely get a sync tool.


Sent from my iPhone using Tapatalk

[nickon]

Pulled the carbs of the bike and took them apart. They looked pretty clean to me.

 

Main jet seemed to have the number 1.9 on it and the pilot jet 2.8, is that possible? Are these stock jet sizes?

I also measured the floats before I took em off and they were both set properly at 21mm (although I thought the left would be off because it was leaking fuel after riding the bike).

Jet needle was also set properly at the third groove on both carbs.

I also pulled the T.O.R.S. off and gonna order a delete kit along with the carb sync tool so I can put the carbs back on without T.O.R.S. Is there anything else I can check in the meantime (parts shipping from US to Belgium will probably take a while). Or should I just wait untill I'm able to put the carbs back on without the T.O.R.S. and see if that resolves the issue?

Thanks already.

Edited June 3, 2017 by nickon