Upgrading to bottom mount 125cc

[l0new0lf]

I been wanting something a little quicker than a 50cc and after having a bbk last for less than six months I figure this was the safest route to go... I picked up a 125cc engine off a fiddle ii a couple days ago on fleabay and it just shipped today from the UK. I can hardly wait. The engine needs a little patchwork/welding to repair/replace the rear shock mount which busted but nothing much beyond that hopefully. I also picked up the carb for it. Anyone know if a 50 cc exhaust would fit? Im guessing it's probably a no go but ill know soon enough. Will keep you guys updated as things progress.

[noday]

I looked for one of those for a few months but never found one for sale.

congrats and keep us posted.

I am not sure it is a direct bolt in for a 50 frame. looks to me like it uses a mounting bracket similar to the top mount GY6 150 from pics and illustrations in the service manual

exhaust ? you will need a 150 size and may have to do some mods to get a GY6 exhaust to fit

here is a link for the full shop/service manual if you do not already have it.

koen.destemvandebasis.be/Moto_Sym/Sym%20Fiddle125%20Service%20Manual.pdf

[l0new0lf]

I had the manual but had NOT noticed the mounting bracket noday so thanx for pointing it out. Im pretty sure the seller included the mount with the engine at least it looks that way in the photo he sent me. The factory air box was not included in the sale but is still available but im hoping the 50cc box will suffice/fit. I have a 10" 3.50 rim/tire so Im hoping that'll match up okay. The U.S. version of the fiddle comes with a 10" 3.50 as well. My only concern is this rim came from a scoot with what i believe were 105mm brakes and the fiddle is 110mm. Can anyone shed any light on the liklihood of the rim fitting or not? I was trying to keep this on the cheap but like anything there's bound to be more than a few monkey wrench's thrown my way. Does anyone know of anyone who has attempted this mod before? I've seen a few message boards with chatter regarding the 125cc swap but no pics or proof.

[noday]

over all that engine is more similar to a GY6 150 than a 50 so I think you will need a 150 type wheel.

also know that any SYM specific parts will have to go thru a SYM dealer or thru thru someone in Taiwan. there is a fairly active SYM forum, but few of the people who post there do much in the way of engine mods.

you will probably have a better match if you use a gy6 150 air box

I looked for other threads last yr on this same topic and never found any one who actually did the swap.

[l0new0lf]

Got a pic of the elusive engine mount off the 125cc fiddle ii skydrive.live.com/embed?cid=BECE304979329C7C&resid=BECE304979329C7C%21664&authkey=AAFjDLT1DFnDyQQ [/img]
Im unable to do any measurements of the mount as it's still in the UK. Unfortunately, it wasnt included in the original shipment with the engine but it looks promising judging from the photo. It was damaged in the accident which broke the rear shock mount as well but hopefully with a little heat and patience it'll be fixed and bent back straight. I also picked up the muffler, shock and airbox as well from this fiddle ii. Now it's a waiting game as everything needs to be shipped. So between the wait and finding the time to work on this this is looking more and more like a 2+ month project...Damn monkey wrenches. To be continued...

[Deleted]

that doesnt look anything like the fiddle mounts ive seen.

[noday]

that does not look right to me either.

[l0new0lf]

Maybe there are different variations of the part? Can someone post a real photo of the part and not just something from the manual? He hasnt shipped anything yet so let me know sooner rather than later if possible. The engine arrived today and it looks like I dont even need the engine mount anyway. The mounts on the motor even fit the 50cc bolt used to attach the engine to the frame. I'm just having trouble lining everything up so I can slip the bolt thru. The front seat bucket support bracket on the chasis is not high enough to clear the cylinder head assembly. The bracket just needs to be raised higher and rewelded. Easier said than done but doable. Perhaps a long case 50cc frame would be a perfect fit. Anyway, Ill try to post pics tomorrow. I have another frame which looks like it would be a better fit, also a short case, but the front seat bracket is higher. I might explore that tomorrow but I just havent decided if I want to tear a perfectly good bike apart to attempt this.

[l0new0lf]

Changed the oil and tranny fluid and started the engine up today for the first time. It was missing the kick start lever and the starter but I was lucky enough to find a used starter at one of the local scoot shops. Seems as if the parts so far at least are all very "gy6 friendly". There's no exhaust yet but it started right up with a 50cc airbox duct taped on. It's just temporary of course I'm just happy it started. I had zero luck finding a 10" 3.50 rim that would fit. Larger rims fit no problem but I would prefer to stick with a 10" because I can not get anything bigger to fit up front. Anyone have a 10" rear rim laying around that would fit 130 mm drum brakes? Sym wants $130 w/ shipping for a cali classic rear rim (which was cheaper than the fiddle ii rim). And that just seems a weee bit on the high side.

[l0new0lf]

Finally got the engine bolted in. The additional engine mount was not necessary. It took alittle work getting everything to line up though. I think with a bigger frame it would fit without any effort whatsoever. I wound up going with a 13" rim w/ a 130/60 tire in the rear and a 10" 3.00 upfront . I wasnt planning originally for this to be a ratrod but the look is starting to grow on me. The exhaust is nearly complete. I wound up using a 50cc pipe and muffler with a few mods. It was a bit of a challenge because the exhaust port did not line up with the space in the 50cc chasis allowing you to do a straight drop with the pipe. I choose to use the exhaust manifold and a 1/2 inch of pipe from the 50cc pipe and just piecemealed/welded galvinized 90 degree pipe/fittings from home depot to get it to work. It's not the prettiest pipe but I was going for function not form. Also a single pipe given the twists and turns would be impossible to remove should you want to change a tire or do whatever. Next I gotta get the front brake working (I made the mistake of not swapping out the brake fluid and had the site glass crack). Today I sealed it with some jb and will attempt to bleed them tomorrow. Posted some photos of all the progress of the project so far here: sdrv.ms/S8VJrX I decided not to get any more parts from the donor bike in the UK and went with a stock 150cc airbox which should arrive any day. Took the cvt apart and discovered the kick start needs some new parts to get it working reliably. The variator is stock but like new but had only one out of the three glide keys in place (Other two were completely missing). Must have been run that way for a while because there was only one roller which had flat spots. Stock weights for the fiddle ii must be 14g. Clutch was like new as well. It's pretty obvious now the donor bike had either been sitting for a long time or wasnt ridden much at all. Anyhow, I ordered 13 gram sliders along with 3 glide keys, a chrome kick lever and a kick idler gear. Im just waiting on those parts. Next big decision is what to do regarding the broken rear shock mount. I can either have someone repair the shock mount, ez but not much fun, or just fabricate a bracket and attach it using one of the cvt cover slots directly behind the mount along with a tranny bolt. Im just not sure if it'll be strong enough.

[Deleted]

awesome cant wait for a power report

[Deleted]

omg dont run it with that fan shroud off for long or your top end will be wasted

[l0new0lf]

I took a few more photos today of the progress and posted them here: sdrv.ms/S8VJrX I painted the exhaust pipe and got the broken shock mount fixed. Got most of the body panels back on not without having to make some modifications to get most of them to fit around the bigger engine. I had to cut part of the battery compartment on the floor board off to get it to fit. The other side panel on the airbox side needs to be trimmed to fit around the bigger air box. But those are all minor details at this point. All I can say is she's defnintely a runner. I've had her up over 70 mph gps verified. With two people it'll do 60 which Im more than satisfied with. I've managed to nearly wear out a new set of variator glide keys within a month?! Not sure if this is typical, I'm guessing not but Ive ordered some dr pulley glide keys which hopefully will out last these and do the trick. I also replaced the stock belt it came with with a gates equivalent. Ive been unable to locate a kevlar belt as of yet though. If anyone knows where I can get one (size 799-19-28) please let me know as the "genuises" over at Sym dont even know if they make one and referred me to someone who apparently doesnt return phone calls. I'm still waiting to be approved by the "powers that be" which Im guessing is Mike Hickman so I can ask a few questions on the Sym boards. Overall Ive been very unimpressed both with the knowledge and competence of the USA Sym staff which apparently comprise of a whopping three people.

[inuyasha]

Hi
You do know that technically your scoot is now classified as a motorcycle in all 50 states and must be registered insured and you would need a motorcycle endorsement on your license to ride her legally
Take care and ride safely
Yours Hank

[l0new0lf]

Oct 7, 2012 15:22:56 GMT -5 inuyasha said:

Hi
You do know that technically your scoot is now classified as a motorcycle in all 50 states and must be registered insured and you would need a motorcycle endorsement on your license to ride her legally
Take care and ride safely
Yours Hank

I am aware of the law Hank and would never dream of circumventing any of them. :thumb: Anyone know about the belt?