|
|
Post by axis925 on Mar 17, 2023 20:19:50 GMT -5
I bought a yamaha axis 90cc and was told it had a 101cc cylinder.. the seller screwed me over pretty good when he brought it to me the back tire was flat so I couldn't really ride it before I bought it but it had started right up..This bike has very small tires and someone but long straight valve stems on it. Finally after trying everything I could I called a mechanic to come take the tire off
Well that's when things started to go wrong as soon as the mechanic started to take the side of the exhaust screw off he had said I must be missing an exhaust screw on the bottom. Sure enough It was but also a chunk of my cylinder was as well and I was told it wasn't fixable
So I contacted seller he claimed he was going to help solve this problem and the past month and half I've been completely ignored "nice guy"
So this is when things get strange I take the shroud cover off to find a bws100/grand axis100 cylinder that had been built to fit.. I posted pictures in a local fb scooter group here in Massachusetts. I also searched the internet none stop and there's nothing about this.
No one really new much about how the get the cylinder on in the fb group but a week later a dominican guy recognized my bike he said my bike came from the dominican republic witch I pretty much figured..
I could talk on the phone so I had to translate by typing he pretty much told me that they take bws100 racing crank inside the 90 3wf case and also use bws100/axis100 cylinder.. that's the part I couldn't understand for a while because you cannot mount it to a 90cc engine there is a 2mm difference.. I don't know anything about modifying engines..
this guy's friend helped explained that they put the bws100 crank inside and take the cylinder and drill the stud holes a little bigger so it's able to slide down the studs..
But I really need your guys help and opinions but I have one problem...
I don't know the size of the crank inside and I can't split a case or have the money for someone to replace a different crank
Can I just buy a 54mm cylinder that will bolt right on that is the same hieght?(or can't because of crank)
Do I have to buy a bws100 cylinder and have a machine shop drill larger holes?
Or do I just buy another 3wf motor I found that runs with original 90cc motor on it for $250? (Real rough shape but I would no what is inside)
PLEASE I NEED YOUR GUYS HELP THIS IS MY FIRST TIME POSTING IM GOING TO POST PICS ONE I FIGURE IT OUT
|
|
|
|
Post by axis925 on Mar 17, 2023 20:42:08 GMT -5
|
|
|
|
Post by axis925 on Mar 17, 2023 21:06:09 GMT -5
Here is the same stock motor for $250 that has seen better days   |
|
sinfull
Scoot Enthusiast
Posts: 361
|
Post by sinfull on Mar 19, 2023 1:16:20 GMT -5
Good question. I would start by pulling the cylinder and actually seeing what is inside. Have to look and see what the rod length is. Is the rod the same length as the 90, and the extra cc are in the bore diameter, or is the extra cc in combination with the rod length and bore.
If rod length is same then you maybe could use a stock 90 cylinder, if rod is different length than you would have to change crank
|
|
|
|
Post by axis925 on Mar 19, 2023 7:19:18 GMT -5
Good question. I would start by pulling the cylinder and actually seeing what is inside. Have to look and see what the rod length is. Is the rod the same length as the 90, and the extra cc are in the bore diameter, or is the extra cc in combination with the rod length and bore. If rod length is same then you maybe could use a stock 90 cylinder, if rod is different length than you would have to change crank I know the basics with scooter and hate to sound like a noon but how can you measure the rod without spitting the motor? I feel it would be hard to get a accurate reading with just a few mm difference. I don't belive it's a regular axis90 crank I'm almost positive it's a bws/axis100 crank and may be a longer racing crank.. It maybe a regular bws/axis100 or a racing bws/axis100 race crank. I've thought about this alot and there doesn't seem to not be anyway of ME being able to fix this! I may sound stupid but does cylinder height go by the number of fins? It seems like ever 90 has 7 and everything around 100cc has 8 if I fix this bike I want to make sure it's I 100-110cc I'm best off because the bike is all set up and tuned for that Every way I look at it I'm confused... I can't just get a regular 54mm for 101cc bbk built for a 90cc because the wrist pin is most likely 14mm instead of a normal 12mm because the piston must be 52mm.. I can't get anything with a 52mm because because it won't fit on stud pins I would have to drill the stud hole bigger on the cylinder.. Only 2 ways I see this working is if I got another 52mm 101cc without spitting the case is 1. Another stupid question do they make anything that go's on a wrist pin to make it 2mm bigger like a bairing maybe? If so Get a 101-115 bbk for a 90 that way it would just bolt down 2. Buy another 52mm bws/axis100 cylinder(same height)..Buy a 54mm cylinder head so it will line up. That way I wouldn't have to worry about the wrist pin/piston size. Then drill the stud holes Buying the stock 90cc motor with cylinder that is the same motor mine. Other questions Does anyone know why there is a piece of metal welded on the side of my broken cylinder (I'm guessing for support) but would I have to weld a peice on a new one? Could I drill the hole or is this something I should bring to a machine shop? How would i measure the rod without opening the case? Would buying that plug and play 90cc motor for 250 be worth it? |
|
|
|
Post by 90GTVert on Mar 19, 2023 7:40:21 GMT -5
With it not running well, you don't know if it ever ran great. Could be a botched job that never worked right. Could be a runner if it's done properly. It seems like the easy way would be to find a horizontal Minarelli engine in excellent condition and bolt that in; considering you say you don't know anything about modifying engines. Heavily modified stuff like this gets more complicated than just bolting on a big bore kit because you have to make sure all sorts of specs are right, or close enough, and may have to machine parts. If you're going to rely on a machine shop, it could potentially get expensive.
It looks like the right 49cc would bolt in. Those should be common enough to find something in good shape. Not sure about the Axis rear wheel fitting. I don't know much about them. You can also find some older youth ATVs that had the 50, 70 and 90cc versions of the horizontal Minarelli if you want to look for a larger engine to bolt in.
|
|
|
|
Post by aeroxbud on Mar 19, 2023 12:04:43 GMT -5
You should be able to work out which crank it is it they have a different stroke. Put something like a zip tie down the plug hole and measure the stroke from bottom dead centre. To top dead centre. You can put marks on the tie to help.
|
|
|
|
Post by axis925 on Mar 19, 2023 13:31:21 GMT -5
You should be able to work out which crank it is it they have a different stroke. Put something like a zip tie down the plug hole and measure the stroke from bottom dead centre. To top dead centre. You can put marks on the tie to help. So do you mean take piston off and tie a zip tie around the connecting rod?... sorry im a little confused |
|
|
|
Post by axis925 on Mar 19, 2023 13:44:44 GMT -5
With it not running well, you don't know if it ever ran great. Could be a botched job that never worked right. Could be a runner if it's done properly. It seems like the easy way would be to find a horizontal Minarelli engine in excellent condition and bolt that in; considering you say you don't know anything about modifying engines. Heavily modified stuff like this gets more complicated than just bolting on a big bore kit because you have to make sure all sorts of specs are right, or close enough, and may have to machine parts. If you're going to rely on a machine shop, it could potentially get expensive. It looks like the right 49cc would bolt in. Those should be common enough to find something in good shape. Not sure about the Axis rear wheel fitting. I don't know much about them. You can also find some older youth ATVs that had the 50, 70 and 90cc versions of the horizontal Minarelli if you want to look for a larger engine to bolt in. The scooter starts up and runs and was built buy someone well known for one of the best builders around Boston. But I'm not going to ride it with a the exhaust attached like that and the condition the forks are in (the p.o.s that sold it to me forgot to bring the new forks he bought for it. Told me he would drop them off to me but because now he's suppose to buy a new cylinder for me I've been completely ignored. So looks like I'm buying new forks aswell) |
|
sinfull
Scoot Enthusiast
Posts: 361
|
Post by sinfull on Mar 19, 2023 14:00:23 GMT -5
Maybe try to contact the original builder and see what they actually put in the case. If well known should be able to atleast get you the information you need.
But Brent is right, anything modified or performance is not going to be a simple twist and go kinda thing.
|
|
|
|
Post by aeroxbud on Mar 19, 2023 14:17:41 GMT -5
You should be able to work out which crank it is it they have a different stroke. Put something like a zip tie down the plug hole and measure the stroke from bottom dead centre. To top dead centre. You can put marks on the tie to help. So do you mean take piston off and tie a zip tie around the connecting rod?... sorry im a little confused No you don't need to take the piston off. You just need to measure the distance travelled. But With that and the wrist pin size you should have a good idea what crank is fitted. |
|
|
|
Post by axis925 on Mar 19, 2023 14:20:24 GMT -5
Maybe try to contact the original builder and see what they actually put in the case. If well known should be able to atleast get you the information you need. But Brent is right, anything modified or performance is not going to be a simple twist and go kinda thing. He is well know for building and importing scooters amongst the Dominicans. He does not have social media but I talked to a few people.One person gave me his number but I've got no answer or any texts back. It's very frustrating but I'm going to keep trying! |
|
|
|
Post by axis925 on Mar 19, 2023 14:31:07 GMT -5
So do you mean take piston off and tie a zip tie around the connecting rod?... sorry im a little confused No you don't need to take the piston off. You just need to measure the distance travelled. But With that and the wrist pin size you should have a good idea what crank is fitted. I know it must be a 14mm wrist pin because in that bws/axis100 and would have a 52mm piston.A axis90 is a 12mm pin.. but if it's after market I'm not sure .. Hate to sound like a noob but there's alot of bws aftermarket size cranks.. What does it mean when it will say 49mm(+3) or 52mm(+4.2) |
|
|
|
Post by aeroxbud on Mar 19, 2023 15:30:49 GMT -5
That's probably the increase in stroke compared to the standard crank.
|
|
|
|
Post by 190mech on Mar 20, 2023 4:08:47 GMT -5
It would be easy to pull the top end to see what you have. A 14mm pin piston can be bushed to a 12mm size, but a BWS100 crank is too big to fit a 90 case unless it is bored out paper thin (I did it once!),possibly they used a 90cc,48mm stroke crank with a BWS100 rod..Any way about it makes a patch job build sure to fail soon..The 100 was not a good platform for performance builds as parts are very limited and the reed and cylinder do not have a good flow design,,
|
|
