Category Archives: Service data

Electrical Theory…

Electricals on bikes, everyone hates them right? Why? There is a perception that it’s difficult to understand and is some sort of black magic. It would be easy for me to sit back here and say it’s all basic stuff with the AG200. The problem is I have been immersed in electronics and technology all my working life – nearly thirty years!  So what I find relatively straightforward others may have trouble getting their head around. I get it.

Problem is geeks and nerds (I class myself a geek, don’t know if I qualify as a nerd!) usually have a bad reputation for trying to explain concepts that they understand so I’m going to palm this one off! Down below are some links to some old Yamaha Training info that I had lying around. This is some entry level stuff that hopefully will give you a basic understanding of how electrics work on most bikes.

Electrical Charging Systems

Ignition systems

CDI systems

Electrical Systems 1

Electrical Systems 2

Electrical Systems 3

After reading all this you should have a better understanding of the electrics of your trusty steed.



A standard top-end rebuild kit.

Greetings for the new year folks, hope you all had a good festive break and the new year is a big one for you…even if we are 3 months into it already!

I thought we would start the year off with a bit of a tip for your basic AG200 overhaul. I say “basic” because there is really nothing too bad going on here. When I had a shed full of these things and old trade-ins and barn-finds seemed to follow me home weekly (daily?!), this was my standard engine overhaul kit that I used to keep in stock.

I found that the AG200s lasted somewhere between 15000 to 20000kms with zero maintenance. And 80% of the AGs I fixed that were from farms pretty much had zero maintenance. Oh, they might of had the free first service but after that – nothing. They would ride it until it self destructed! So what I have listed here is the standard top-end rebuild kit that you would have to put through the engine when it got to this point.

Now you might look at the list I have down below and say WTF! Why so many bits AGman? Well, you have to put things into context. It may be hard for someone coming from a different background to get their head around everything I have listed here, I get it. But we are not talking about an engine that has had periodic servicing done here…its had NOTHING for 20000km. And not normal 20000kms either. No airfilter cleaning, probably a clogged oil filter that at least has restricted oil flow. No cleaning so there is probably baked mud in the cylinder/head cooling fins…its a train wreck!

Here is the thing you need to remember most; anything rubber must be replaced. The biggest issue with leaving oil in an engine for this long is that it turns into an evil destructive sludge. If the inner cases look like they have been painted in varnish then the oil has been in for way too long and the chemicals that build up in it destroys rubber and I suspect doesn’t do a whole lot of good for gaskets either.

As for the parts themselves, you can get after-market gasket kits but I have never really liked them. I prefer the Yamaha originals. The timing chain can be sourced after-market, RK is a good brand. Everything else I would go with Yamaha. Lets have a look…

From this exploded view we will require part 6, 8, 13, and 2×17.










From this view we will need 2, 3 and 4









From below –  2×6 and 12.









From below – 2, 7 and 9.










From below – 7 and 11.









And finally, from below – 9 and maybe 2×11 (see text).










To sum up:

1NU-11181-00       GASKET, CYLINDER HEAD 1

90430-14131          GASKET

93211-45471          O-RING

93210-57634           O-RING x 2

93210-72529           O-RING

5LB-11351-00         GASKET, CYLINDER

93210-13361           O-RING

5H0-12119-00        SEAL, VALVE STEM x 2

93210-09165          AA5 O-RING

4BE-15451-03        GASKET, CRANKCASE COVER 1

93210-14369          O-RING

93210-32172          O-RING

94580-41104          CHAIN (DID25SH 104L)


15A-11603-00        PISTON RING SET (STD)

93450-17044         CIRCLIP x 2 (if you need to remove the piston to clean it)

There are assumptions and additions here; The two valve guide seals are needed because most AGs at this stage have been pretty fumy and there will be lots of carbon in the combustion chamber and the exhaust port. you really should pull the valves out to help with this clean-up and inspect the valve faces. I would strongly recommend a grind to clean up the faces – they will probably need it. So if the valves come out, you will need the valve guide seals.

I have covered mostly consumables here. There are lots of parts that need to be checked as well; are the cam chain tension guides going brittle? How does the cam look? Rockers? Valve clearance adjusting screws? Valves? Was the base gasket leaking? How do the cases look where they join up at the cylinder base?  Lots to cover in a later tutorial…

The rubber parts that go in between the cylinder/base and cylinder/head are critical. Re-use the old ones at your peril! Take a look at the three radial seals on the engine as well – counter-shaft, gearlever and kickstart. If one is weeping replace them all because they will be going hard and failing soon.

Don’t be tempted to replace the o-rings listed here with generic bearing shop stuff – all rubber is not created equal. These need to resist oil and elevated heat. Unless you know where to source these o-rings from, go with Yamaha.

Obviously the part number of the piston rings will depend on the oversize of your engine but I doubt anyone would bother boring an AG200 up to the next oversize. If the piston and cylinder is worn out on one of these bikes then the rest of it will be rubble! Check anyway, and while you are there measure, or get someone with the equipment to measure your piston and cylinder to see if they are within specs.

Hopefully I will be able to do a tutorial this year to show the fitment and little tips and tricks of putting all these bits together. Don’t hold your breath though! 🙂



AG200L (’93) service manual

It seems a lot of folks out there are still getting the early, 6v AG200s back on the road. I have never really bothered with them much because the later ones have electric start, a much better 12V electrical system and other upgrades that make them the bleeding edge in AG200 technology(!).


Discrimination can be a nasty thing though…sooooooo as a service to my fellow AG200 fan-boys/girls, I have been on the lookout for an AG200L service manual pretty much from the time I started this blog. Well it’s happened and now all you 6V blowhards can stop hassling me! 🙂

I just spent a couple of hours scanning this manual and both my arms feel like they are about to drop off so I hope y’all appreciate this gesture from your kindly AG200 Guru. Yes, there are a few greasy fingerprints on the scan and a bit of bleed through of images on the reverse face of some pages, but hey…it’s FREE! Its not perfect but I think in a lot of cases it’s better than the other factory service manuals that I have listed on this site.

The real reason I wanted to get this manual up is so my mate in Poland who collates all my AG200 info into a CD and flogs it on Ebay, can complete his collection. You go buddy!

AG200L (’93/’94) service manual

This is how I spend my Saturday nights…I really need to get a life!  🙂



Parts listings…more AG200 gold!

Welcome to the new year of 2015, hope ’14 was a good one for you. I thought I would start the new year with a bang by posting up the AG200 parts lists. I have most of them but thought I would link to an older model (1988), and a newer model (2003). This will help you bypass the incompetent Yamaha spare parts guy if you are unfortunate enough to have one in your area! Select your part number and supply him/her with it so they cant stuff it up!

Its also interesting sometimes to enter the number in’s excellent Yamaha parts listings to see what, if any, other Yamaha models use the same part.

Apart from a few new bits on the current AG (2013 onwards), these two parts lists will cover most parts and their numbers. The ’88 manual has the listings for the earlier yellow bikes and the later beige ones, which is handy if you’re after a specific colour part like side covers, guards or a tank.


2003 AG200

1988 AG200



2002 Yamaha AG range brochure

How on earth did the word “brochure” get into the English language? Go and do a search for the definition. French origins of course, itself derived from Latin “…to stitch together” Language really baffles me sometimes. Isn’t there a word we could of thought of for “Sales Literature?”, especially with the talent that got sucked into marketing in the early twentieth century and the American (most of that marketing stuff came from the ‘States) penchant for making their own editions to the English language!

Now there’s an interesting start to a blog post on an AG bike! I thought I’d spice it up a bit because there isn’t really much to say here. If you’re a specs weenie and like memorabilia then here’s a bit of stuff related to the AG200. It’s actually the whole Yamaha, two wheel AG bike range for 2002. What a hoot! Bet it will be worth heaps in years to come! 🙂

Note the AG200E and AG200EA options. My previous posts mentioned the complied version of the AG200 and this documentations confirms that Yamaha called it the AG200EA (A for ADR?). Notice the different headlight? The old AG100 gets a mention too. Another thing of interest; I’m looking real hard at the guy riding the bike on the last page and I reckon it’s Steven Gall. Remember him? Australian Motocross legend? He was heavily involved with Yamaha promotion at the time and I wouldn’t be surprised if it’s him.















And for the truly committed, here is the full resolution download in PDF format but beware, it’s just over 40Mb in size.



AG200L assembly guide

Here’s a little bit more info that I thought I would pass on. It’s the Yamaha dealer assembly manual for the first AG200L. It is still relevant to the new models but the eagle eyed among you will notice the 6 volt battery, the early fuel tap and the split pins used in the axles. I will post up the later manual (if there even is one?) as I come across it.

If you have an AG and the cable routing looks a bit dodgy, you can check this document to see if the cable routing has been done correctly from the dealer – you would be amazed at how many don’t read the manual! All the cable routing info is in the workshop manual that I have already listed anyway, but I still think this doc is cool if you are into these bikes.


AG200L assembly guide



AG200 service information

Maintaining and repairing motorcycles is just as enjoyable for me as riding them…I find it relaxing and satisfying when you know a job is done right. But maintenance and repairs can be frustrating, detrimental to your machine or even dangerous to yourself if you don’t have the required tools and service information. Good tools and service info are two must haves for any work on any bike in my opinion. So I have posted all the relevant data for the AG200 so you can access it to help you out on your AG journey. I will add more info as it becomes available and anyone who thinks I’m short on something just let me know.

1997 3GX – link to the first PDF format manual that I have found. It’s a scan but still very helpful.

3GX ’03 update – link to the updates for ’03.

3GX ’08 update – link to the ’08 updates.

These are manuals related to the Australian models but the rest of the world should be pretty close. They are also not as comprehensive as one might think but I will try and cover some of the discrepancies as time goes on.