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Do you have a hot tip for Maico maintenance, race setup, overhaul, paint or anything at all. Please share it with all of us, you 'll get the credit and the rest of us will be forever indebted to you!
Just email me your tip and I'll post it. Thanks!!
I must add the standard disclaimer that tips don't work for everyone.. But what the heck, give us a break we're trying here. We all know Maicos are a different breed of motorcycle
and the one that came next off the production line
after yours may be different.
If your front brake dont work very good try reversing the wheel, i.e drum on the left it rerouts the cable and reduces drag on the inner cable.You'll need to make another brake stay but it's worth it.
My bikes will outbrake any other vintage mxers.
I currently race a 74 440. I raced a 400 in the 70s . I have an aggressive riding style ( style ? ) whatever, anyways my fork springs seem to sag after 6 or 7 races. Here in Florida, lots of whoops. I take the old spring and cut off about 11/2 inches and grind down till it matches and is flat. I use this as a sort of preload. I run 30w oil in the forks. You might have to increase the oil weight until you get the correct feel on the rebound, depending on your weight and riding "style" (there's that word again ). Another trick I found helpful was I eliminated the compression release. I run a PVL ignition , which is one the best things I have ever bought for my German rocket and myself. My release continued to get loose even after repeated episodes with dear old Mr. Loctite. My bike starts on the 2nd or 3rd kick and DOES NOT KICK BACK ! Adolph , Willi and Gerrit never used them. If it was good enough for those guys , it's good enough for me. One last thing, throw away that regular run of the mill 2 stroke oil. Use a castor type. I use Maxima and my Teutonic Trencher loves me for it, smells good too. I wonder if Renuzit air freshener company would consider this fragrance. I know I'd buy a case. Burnt castor smells like, like, VICTORY ! Any tips or comments, e-mail me at PAN1955 at AOL.COM. THANKS, Skip Harley
TIP #2 The 490 has a powerband to pull tree stumps out with, but, unless
it's perfectly controlled, up goes the wheel ! In any case, on the 81 490
there is an aluminum adapter (with lots of slots and a plastic insert)
between the carb and the engine - TAKE IT OUT. If I remember, the carb
can be bolted directly onto the engine, without the spacer. I think the
carb had the female side, then a short male:female part. Then the female
part of that
adapter went onto the engine. If you take spacer/adapter out, the intake tract is maybe 1-2" shorter. The goal here is to make the intake tract as SHORT as possible. The carb boot may be stretched a little but...MONSTER LOW
END WITHOUT EXPLOSIVE POWER...you'll be surprised.
TIP #3 Also on the 490 engine, forward momentum can best be gained with rear wheel hooked up, motor running sloooowllyy. Retard the timing (experiment) until you get the 200RPM torque that will holeshot a new 250.
TIP #4 (JETTING) A lot if not all of the 490's came from Germany with richjetting. One reason they do that is to keep them from seizing no matter where they are finally sold and delivered. However, unless you live in Alaska, the jetting is usually too rich down low. If it runs rich, especially off the bottom, it will not be tractable or easy to ride - there's nothing that says a bigger bore means harder to ride. What happens is it'll idle a little or not at all, then you crack it open and it'llsputter, then all of a sudden it'll take off. What is happening is it is running too rich down low, then loading up (saving gas for later) and then when it is getting more air, it'll take off. A little bit like lighting a firecracker in that it all goes at once.
First I need to define rich and lean. Remember that air and gas are
never input in equal quantity, volume or weight. If I remember, the best
ratio for power is about 14:1 (air:gas). Also remember that since oil is
mixed in with
the gas, a 32:1 gas:oil ratio will make an engine run leaner than a
50:1 gas:oil mix. The reason is that the 32:1 ratio has less gas per volume
than the 50:1 does, and since that ratio (whatever you use) has to go through
same jet size (explained later) then a 50:1 gas:oil ratio will make anengine run richer...however this type of tuning is barely noticable. Stickwith one ratio ALL the time. Mix the whole container of oil as that will
make it consistent. I use a 16oz bottle to 5 gal of CAM2 for all my girls, Imean bikes - 96CR250, 96YZ300, 98KX250, 81 490, 2-83 490's.
Ok, so here we are:
rich - more gas than needed
lean - more air than needed
To fix this and any jetting (I personally like Bings) problems it is very
helpful to understand what each carb part does:
- air screw: allows air in while idling. cw is less air ccw is more air.
Affects idling and just off idle.
- pilot jet: allows gas in from just off idle screw (1/16 throttle) to 1/5
maybe. Bigger # = more gas = richer. Rarely bigger # means leaner.
- needle: is tapered, so any more throttle allows more gas. Think of it as an ice cream cone that slides into main jet. There are different taper patterns too though 99% of the time we can use stock needle.
- needle clip: raises or lowers needle
- slide cutaway: allows air in at some/any throttle setting. Various tapers here too though never usually need to change.
- main jet: Allows gas in at many throttle settings as needle goes up and then lets in more gas. Primarily 1/3 to full throttle.
- air filter: may restrict air if too dirty making mixture richer.
- cylinder to carb fittings (reed cage): if screws come out you may seize engine if too much air gets in (without being mixed with gas as it doesn't go through carb but around it.
OK - HOW TO JET YOUR BIKE:
1st, I don't believe in reading plugs, they come in different heat ranges
anyway...it still will be good, after you think the bike's jetted perfectly, to check the plug, it should be brown/black and NOT white. White is WAY too lean or too cold of a plug. B8 NGK is a good plug type. I listen and feel the engine while riding. Listen for pinging. Use CAM2 if you can - it smells good anyways. If only they would make a woman's perfume from that smell ! I was jetting my YZ300 a few weeks ago and it sounds good while in nuetral, but riding it was another story. The reason - while riding, there is a load on the engine. Load means the engine would be going faster if it wasn't stopped by rear wheel traction. Therefore while riding the engine tends to be loaded down (and maybe richer)...
STEP1 - ride the bike, putt around. If you can't go slow without the rear wheel breaking loose it may be too rich down low. I used to ride my 490 in the snow - great fun with 100 foot donuts ! Idle and just off is the MOST important part of an open bikes powerband. The reason is, that's where a lot of traction (forward acceleration) can be had. Also, the slower the engine goes, the more traction any bike will have. Actually, I may add, the further apart the power pulses are, the better for traction. So, at 3000RPM, a 4-stroke fires at 1500RPM while a two-stroke fires at 3000RPM. That's why we need the engine to go fast at low RPM. Another good way to test is riding in the mud as there's very little traction.
Start with the idle screw, turn it ccw until when idling (give it a little gas and then let off) it'll ping just barely. Then if it's still too rich down low it will need to have the pilot jet lowered (usually a smaller #) and try one size at a time. Then once the idle up to 1/8 throttle is clean, move to higher rpm's. Next is the needle/clip position. This affects 1/8 to 1/4 maybe more. If you raise the clip on the needle you make it leaner as the needle sits lower in the main jet. You can hear and feel pinging, which won't hurt it for very short periods. If it pings you know you went too lean so go back to pits right away and go back richer.
If it won't run wide open then the main jet needs changing. Remember the main jet also affects what the needle does as the needle sits in the main jet - a lot like an ice cream cone as it's tapered. Pinging also sounds like ringing as the engine, if you gas it while stopped in nuetral, then let it back down, it won't sound even but will go faster then slower as it goes back down to idle.
From my exp, most open bikes are too rich by one size on the pilot jet.
Here's another good way to test jetting. Get out where there is some space, and get the bike moving slowly in 1st or 2nd. Then put it in 3rd or 4th so the bike is idling but still rolling along a little. Then gas it little by little and see what the engine does. If it doesn't climb all the way to top end without hiccupping, re-jet something !
Oh yes, air temperature affects jetting. The hotter it gets the richer your bike will run, as hot air is not dense air. That's why hot air rises. In the winter time (40 outside) the bike may run good but make sure it's not too lean. Altitude affects jetting...the higher you go, the thinner the air, and the richer it'll run as you can't get the same quantity of air thru the same size jet anymore. Humidity affects jetting too. The more humid it is the more air that is going in there, and the leaner it'll run. Humidity sometimes acts wierd though as more water is going in too.
It would be nice if NW Maico or somebody would allow us to trade jets as once it's done you don't need them any more. We could mail one in and ask for a trade...
The goal here is a tractor engine down low so the bike will gain enough speed at low rpms to keep the rear in the vicinity of the earth at higher rpms...
Michael Yelland mjy78 at eudoramail.com
Tnx Bob for the new section for info to be passed on. Heres mine. With the recent venture of getting back to Maico's and bikes after a 22 yr lay-off, here are several things I have remedied with my involvement on now owning 2 83 490 Maicos, 1 83 250 Maico, and also building/working on a neighbors 2 490 M-Stars. Have I been busy. Item 1. In the manual for the 83 on Ohlins adjustment procedure, they say rotate (turn) the rebound adjust knob on the bottom as mounted on bike, to the right all the way and then turn back 6 klicks to start. WRONG! You have to rotate counter clockwise (left) all the way for full damp and then rotate clockwise (right) out to 6 klicks (or more) for a start point of stiffer or lighter rebound damp. This is for the Ohlins with Grooved knob at the bottom of shaft. Item 2. On the carb to airbox rubber boot that seems to rot rather easy, to patch up the splits and save $50 i have used a tube of Shoe-Goo which will glue it all back and seal the splits by spreading some into the accordion grooves and make sure a point of contact are glued. This will have a tendancy to stiffen the boot a little but it will work and is permanent compared to duct tape etc. Thats it for the moment with more to come. From Earl Reinoehl firstname.lastname@example.org
When I repainted my 77 125 (red), I wanted the paint to be as close to the factory as possible, if not a perfect match. Fortunatly the bike had seen very little sun, therefore really showed no signs of paint fade on the tank. I was able to take the tank to my local auto paint dealer and they scanned a 2 inch sq area on the tank several times to come up with an average reading. The computer the crunched the numbers and kicked out that it was a perfect match with a still current color. No custom mix necessary. The color codes that it kicked out were for a urethane paint. Here it is- email if you have any questions. Bob Lovell
Dupont Paint (quart) 1996 Monza Red
I scanned a yellow 74 with what we thought had the orginial paint on it only to find out later that it had been painted a number of years ago. So this may be a slightly different color than the orginial yellow. But to my eye it looks like a terrific match. If you wanted to use it I don't think you would be disappointed.
Dupont Paint (quart) 1996 Pennzoil Yellow
I first raced Maicos in the early '70s, and learned to nut trust locknuts, lock washers, or even Loctite-d fasteners. Hey, these things VIBRATE! One special area of concern is the little nut that holds your air filter in place. I had one work its way loose, get sucked into the carb where it jammed the slide wide open just as I came off a jump, and the closely-followed crash kicked the nut into the cylinder where it spent 4 laps turning the piston and cylinder into expensive scrap. Definitely not the hot set up. So now that I'm back to racing Maicos (a '73 400 and a 74-1/2 GP 400) I never fail to use fresh lock nuts on the air filter thingie, and then slip a piece of fuel line onto the threads above the nut. It's probably overkill --- like wearing a rain coat AND having an umbrella --- but it's something I do automatically. You can also use fuel line on the axle adjusters. Besides ensuring the nuts will stay put, it also keeps the threads clean which definitely speeds up chain adjustment.
Mark Thompson email@example.com
Bob - I love your Maico web site! Thanks for keeping it up. However, that is not the reason for my writing. I would like to offer the following Maico clutch wisdom:
I read Clint Welsh's clutch fix solution with keen interest because I have also been dragged into the starting gate by my GP 400, unable to snick it out of gear until the starter finally dropped the gate onto my front wheel. Damn! There they all went with me thrashing around in the gate. You'd think they'd all just wait a few seconds for a guy to catch up! But no, they didn't even notice. Then in the pits I was teased for not being able to time the gate drop. I didn't want to admit that I didn't know how to set up a Maico clutch, so I just slinked back to my truck and vowed to get it figured out before the next race.
What I learned upon disassembly of my clutch is the solution to all you troubled Maico owners, and it is more simple than a modification. It is as simple as assembling the clutch in the right order.
What I noticed upon disassembly was that the driven plates were warped. Obviously that had allowed the driving and driven plates to touch, even with the clutch disengaged. That is why it dragged. I know they weren't warped when I assembled the clutch because they were brand new. As a matter of fact, that is why I installed new ones; the old ones were warped as well. Are you starting to get the picture here?
Somehow I had warped the new plates upon assembly. As you all know, there are two circlips that hold the clutch stack against the spring pressure of the belville washers. After some experimenting and warping of more clutch plates I realized the problem: I had been relaxing my clutch tool after installing only the first circlip so that I could position the last two plates and final circlip under the tool before compressing again to fit.
So here is the solution: stack all plates and circlips into the clutch basket before compressing the tool and DO NOT relax it until all parts are in place with the circlips snapped into their groves. You may still have a heavy pull on the clutch lever, but it won't drag any longer. No longer will you have a legitimate excuse for letting the gate fall over your front wheel.
Ron Winget rwinget at lakefield.net
any maico paint is the same as volkswagen colors.check out paint catalogues for your particular year maico with same year vw colors. example;any red frame maico was painted with vw mars red.my 73 450 was vw signal orange. check it out. regards con erskine
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