Panterra Cafe/Street conversion

[alex_in_az]

I love the Panterra, but I don't ever take it off road and the knobby tires don't let me get the best out of it on the street. so I decided to do a street conversion to it. I got a seat, tank, pipe, pegs and side panels from Taobao.
I started by looking for replacement tires, but the 21" wheel was hard to find tires for plus it just didn't look right. So I found a replacement front wheel at a local wreckers from a 1975 CB200t. This had a smaller disc brake than the Panterra with an incompatible bolt pattern. I re-drilled the bolt pattern and turned a spacer to get the correct offset for the disc.
The new front wheel lowered the front end, but it wasn't where I wanted it, so I replaced the handlebars with clip ons and allowed the forks to protrude thru the triple tree to mount them, this further reduced the front end height and gave me the look I wanted.
The rear needed to be lowered as well, initially I was going to reduce the number of coils in the mono-shock, but after running a few spring calcs I decided the best thing to do was to leave it alone and modify the frame instead.
The tank mounts were similar, but in the wrong place. So I lowered the front ones and raised the rear to compensate for the change in tank shape and lowered rear frame.
more to follow as it progresses

[alex_in_az]

OK here's a couple of more pictures, I shortened the seat rail to fit the new seat, and placed the pipe where it wants to be. I can't fit the exhaust until I get all the 225 conversion parts for it as the exhaust port is too small for the pipe.
I removed the old pegs and am running a set of CG125 pegs that mount under the motor.

[Weldangrind]

You turned a spacer? Please tell us more! Do you have a lathe at home?

I love what you're doing with your bike. Where did you get the seat? The Acerbis headlight looks terrific, and gives it a sort of street fighter look.

Can you spare your old parts? Carguyty could use the seat and old exhaust.

[culcune]

I like what is happening with the Panterra! I wish I had known--I might be parting out the TMEC now that a new one is on its way, and I happened to have a brand new rear wheel/tire (a few hundred miles on it) and a brand new front tire that has not been installed (17" both front and rear).

However, I might just keep the bike as is, and figure out the clutch since I have the luxury of time (don't need that bike to commute), and have a spare bike.

[alex_in_az]

You turned a spacer? Please tell us more! Do you have a lathe at home?

I love what you're doing with your bike. Where did you get the seat? The Acerbis headlight looks terrific, and gives it a sort of street fighter look.

Can you spare your old parts? Carguyty could use the seat and old exhaust.

I got the seat from here http://item.taobao.com./item.htm?spm=2013.1.0.0.M12gsz&scm=1007.10011.531.0&id=36910300697&pvid=9e0577dc-651e-43d6-a52b-ff961d86675f the seat base is a stock CG125 one by the looks of it and It's pretty good quality.
I don't have a lathe at home, but am a Mech Eng at a small aerospace company, so I have access to a lathe and mill and know enough about running them to do small stuff.
The inspiration for the build is from an old CB125 I had in the 70s, that had a similar look.
The old seat is in excellent condition, I had it recovered about a year ago, the exhaust is trash. I re-welded about 3 times due to vibration induced stress cracks.

[Weldangrind]

Thanks for the seat link; I passed it to my Bro-in-law to see if he wants to use it on our Roketa Café build.

Is the head pipe from your original exhaust ok?

[alex_in_az]

Thanks for the seat link; I passed it to my Bro-in-law to see if he wants to use it on our Roketa Café build.

Is the head pipe from your original exhaust ok?

no, it's cracked at the muffler flange. also it's only 1-1/8" O/D tubing. I feel that's marginal even for a 125. the new pipe is 1-3/8" O/D

[Weldangrind]

The more i look at your bike, the more I appreciate what you're doing. Do you have a Taobao link for the exhaust and the tank?

[carguyty]

The old seat is in excellent condition, I had it recovered about a year ago,

How close to other brands are these plastic seat pans? It looks plenty wide enough, but the contours are different from the few pictures I've seen my own ride.

[alex_in_az]

The more i look at your bike, the more I appreciate what you're doing. Do you have a Taobao link for the exhaust and the tank?

there's a bunch of different tank colors to choose from http://item.taobao.com/item.htm?spm=2013.1.0.0.uQtuQg&scm=1007.10011.531.0&id=36888286343&pvid=270e6b4d-0024-423a-9e11-8a49b249a8fd

they require a 1975 cb125 filler cap and the standard chinese petcock fits them
pipe

http://item.taobao.com/item.htm?spm=2013.1.0.0.uQtuQg&scm=1007.10011.531.0&id=36888286343&pvid=270e6b4d-0024-423a-9e11-8a49b249a8fd

there's a couple of different styles of pipe, torpedo like I got and a megaphone style. they come in chrome or black

[alex_in_az]

How close to other brands are these plastic seat pans? It looks plenty wide enough, but the contours are different from the few pictures I've seen my own ride.

externally it looks like most of the others, there are studs underneath it to mount brackets to the seat top rails and a fork at the front that hooks underneath the rear tank mount. the distance from the back of the forks to the rear of the seat is about 21"

[alex_in_az]

I like what is happening with the Panterra! I wish I had known--I might be parting out the TMEC now that a new one is on its way, and I happened to have a brand new rear wheel/tire (a few hundred miles on it) and a brand new front tire that has not been installed (17" both front and rear).

However, I might just keep the bike as is, and figure out the clutch since I have the luxury of time (don't need that bike to commute), and have a spare bike.

you don't have any connections to YPG do you? I find myself down there throwing stuff out of the back of C130s and C17s at high altitude a couple of times a year.

[Weldangrind]

How close to other brands are these plastic seat pans? It looks plenty wide enough, but the contours are different from the few pictures I've seen my own ride.

If you decide to go with this style of seat, I'd recommend the matching tank. It might take a bit of fab work, but the contours would be correct.

[Weldangrind]

there's a bunch of different tank colors to choose from http://item.taobao.com/item.htm?spm=2013.1.0.0.uQtuQg&scm=1007.10011.531.0&id=36888286343&pvid=270e6b4d-0024-423a-9e11-8a49b249a8fd

they require a 1975 cb125 filler cap and the standard chinese petcock fits them
pipe

http://item.taobao.com/item.htm?spm=2013.1.0.0.uQtuQg&scm=1007.10011.531.0&id=36888286343&pvid=270e6b4d-0024-423a-9e11-8a49b249a8fd

there's a couple of different styles of pipe, torpedo like I got and a megaphone style. they come in chrome or black

I see the same link twice. Do you have a link to the exhaust?

[humanbeing]

I see the same link twice. Do you have a link to the exhaust?
http://item.taobao.com/item.htm?id=36905012207

[alex_in_az]

http://item.taobao.com/item.htm?id=36905012207

thanks, not sure how I messed it up

[alex_in_az]

If you decide to go with this style of seat, I'd recommend the matching tank. It might take a bit of fab work, but the contours would be correct.

coincidentally, I have a tank that I don't need

[Weldangrind]

http://item.taobao.com/item.htm?id=36905012207

Thanks HB. Do you have a link to performance exhausts for modified CG125 bikes?

[Weldangrind]

Alex, do you think the Honda decal would be easy to remove, or is there clearcoat on top?

[alex_in_az]

Alex, do you think the Honda decal would be easy to remove, or is there clearcoat on top?

nope, IMHO that's not coming off.

[alex_in_az]

I took it out for a couple of laps around the cul-de-sac this afternoon. It has a very different feel to it than previously, the riding position is completely changed and the street tires have a much more positive feel to them.
I don't think I got over 25 on it and I've got to get a new speedo cable to adapt the CB200 wheel to the chinese speedo. I also got a replacement rear light/plate holder to fit on. I'm not running with mudguards either end, because I don't have to.

[alex_in_az]

it was a nice and overcast this morning as opposed to being over 100f, so I decided to take the bike out for it's first run. I did about 30 miles in all and it felt pretty good. It's definitely very chuckable and flicks from left to right very easily. I ended up dropping about 20lbs in weight over all converting it from dirt to street.
I got it up to 62mph per my GPS and that was at about 9200rpm in top, so that's about it I reckon until I get the new engine parts and convert it from 125 to 225.

[Weldangrind]

That's decent speed for a 125cc four stroke!

[alex_in_az]

That's decent speed for a 125cc four stroke!

I think I remember pushing my CB125 up to about 70mph, but I was about 30# lighter back then

[Weldangrind]

I pushed my TS100 to 70mph, but I was 55# lighter back then.

[pchitti]

I want a wheelie pic.... lol
Looks great man!

[katoranger]

What are the next plans? Lowering?

[alex_in_az]

What are the next plans? Lowering?

more power with a 225 conversion and paint. I'm not sure what to do about side panels for it, my son built a 3d printer, so I might have him print me some up. it's pretty low right now, having dropped the front by about 5" and the rear only has about 4" of travel on it.

[culcune]

I like the look of that...I have a spare TMEC enduro which needs to do more than provide spare parts for me. I know that Wade from Excalibur has offered me a new frame and/or engine, so it is tempting to do something with the spare bike!

[Weldangrind]

...my son built a 3d printer, so I might have him print me some up.

Holy cow! :clap:

Is it CNC based, using a router? I'd love to see / hear more about it. Any chance you'd start a thread on it?

[Weldangrind]

It's pretty low right now, having dropped the front by about 5" and the rear only has about 4" of travel on it.

If you want the traditional café look, an early 80's XR200 swingarm would probably bolt on, as it did on my Roketa. You'd only need to weld on upper shock mounts, and you'd have a twin-shock rear end.

[alex_in_az]

Holy cow! :clap:

Is it CNC based, using a router? I'd love to see / hear more about it. Any chance you'd start a thread on it?

it's a Mendelmax 1.5 FDM (fused deposition molding) type. basically it's like a complex cake icing bag http://store.makerstoolworks.com/printers-kits/ , IIRC I paid about $1k for the kit and he built it. he runs it off a laptop and it takes .stl files outputted from any 3d cad program. there are a couple of front end software packages that parse the stl files into slices and convert them into G code.
there was virtually no info and so he had to figure out the wiring and then de-bug the system.

[Weldangrind]

That's fascinating! So, you start with a parent piece of plastic, and then fuse deposition comes off of a roll of filament? If so, that helps me to understand how the Z-axis is accomplished. What kind of thickness can be created?

[alex_in_az]

That's fascinating! So, you start with a parent piece of plastic, and then fuse deposition comes off of a roll of filament? If so, that helps me to understand how the Z-axis is accomplished. What kind of thickness can be created?

the bed size is 8 x 11 and the Z-axis can translate 6", so in theory anything inside that. in reality if you try and print really thick sections you get heat issues that cause warping and dragging the extruder head thru the part. so we normally don't go over about 1/4" thick, dependant on the over all size of things and maintain a 60% max difference between joining walls.
for really large parts, you cut them into sections that the printer can do and then put them together like a jigsaw puzzle using 2-part epoxy or similar.

[lefty guitar]

man that is cool good job lefty guitar

[alex_in_az]

well I finally bit the bullet and ordered a new lifan 200 engine. The conversion of the 125 to 225 is not possible and last weekend I think I blew the rings on the 125 engine. I have no compression at all.
So rather than rebuild the 125 engine I figured I'd get a new 200 engine and put the 67mm jug and ported 250 head that I have on it.
I had to sell the TS185 to pay for it, but that's OK

[Weldangrind]

There will be other TS185's. I had to sell mine as well.

I'm shocked to hear that ring damage could result in zero compression. Even with a burned valve, I would expect some cranking pressure, even if it was only 25-30 psi. It will be interesting to hear about the post mortem.

Have you concluded that you need rearsets, instead of mid controls?

[alex_in_az]

There will be other TS185's. I had to sell mine as well.

I'm shocked to hear that ring damage could result in zero compression. Even with a burned valve, I would expect some cranking pressure, even if it was only 25-30 psi. It will be interesting to hear about the post mortem.

Have you concluded that you need rearsets, instead of mid controls?

the pegs are in a pretty good place for me and I'm 5-10.
there is literally no compression and I assumed rings. the engine just stopped running as I was winding out in 2nd gear. I coasted to a halt and initially thought the CDI had vibrated itself apart losing me ignition. I pushed it home and checked the plug, then the carb and finally put my thumb over the spark plug hole and cranked it.
I didn't feel any noticeable vacuum or pressure as I turned the engine over, so I'm assuming rings. I can see the intake and exhaust valves moving as I turn the engine over.
The biggest problem I have with the bike is it's lack of power. Simply rebuilding the engine will not fix this, so its upgrade time.

[Weldangrind]

I agree, an upgrade is ideal. I'm just saying that I'll be interested to learn what you find when you tear into it (assuming you do).

[alex_in_az]

got the new engine fitted into it yesterday and took it for about 50 miles to run it in. it was mixed riding around town and out to one of the mountain parks we have here. I was trying to hold it to 6k, but wound it up a couple of times. I figure that'll be enough, these engines are meant to be abused. I drained the oil and checked the filter mesh before re-filling with fresh. There were just a couple of small shards of meta in the filter.
It has a tremendous low end, but I think it's starving at high rpms. I'm still running the keihin clone carb and feel like I could do with a 30mm mikuni set up. what are you guys running for jets in mikunis for a stock 200 engine with a UNI type filter?

regards, Alex

[katoranger]

Weld should be of help in that department. Probably some more power to be found with a better carb too.

[Weldangrind]

got the new engine fitted into it yesterday and took it for about 50 miles to run it in. it was mixed riding around town and out to one of the mountain parks we have here. I was trying to hold it to 6k, but wound it up a couple of times. I figure that'll be enough, these engines are meant to be abused. I drained the oil and checked the filter mesh before re-filling with fresh. There were just a couple of small shards of meta in the filter.
It has a tremendous low end, but I think it's starving at high rpms. I'm still running the keihin clone carb and feel like I could do with a 30mm mikuni set up. what are you guys running for jets in mikunis for a stock 200 engine with a UNI type filter?

regards, Alex

It depends on the elevation and the muffler. If it's not terribly restricted and you're near sea level, a 110 main and a 30 slow jet will do the trick. If you're more than 2000 feet, switch the slow jet to 25.

If you're really high (like Denver high), try a 100 main.

[katoranger]

Google says that Glendale is about 1150ft in elevation.

[alex_in_az]

It depends on the elevation and the muffler. If it's not terribly restricted and you're near sea level, a 110 main and a 30 slow jet will do the trick. If you're more than 2000 feet, switch the slow jet to 25.

If you're really high (like Denver high), try a 100 main.

Thanks, I've read you can drill the jets out and the jet size for a 110 main is 1.10mm. Is the slow jet numbering convention the same?
Glendale is about 1100ft.

[Weldangrind]

Yes, the slow and main jets are in mm. I doubt that you'll find bits small enough to drill out the slow jet. I often drill out main jets.

[alex_in_az]

Yes, the slow and main jets are in mm. I doubt that you'll find bits small enough to drill out the slow jet. I often drill out main jets.

OK, so I got a Mikuni for Christmas and it came with 100 mains and 20 idles. fitted it on and took it for a rip. it's definitely running lean, popping in the muffler on coast down and the plug was whiteish.
the closest drill I have in my index is .042", so this would be about a 107 main hole. It idles a lot better than the keihin once it's up to temperature and there's a lot more power to be had. it runs right thru the red line in all the gears without breaking a sweat.

[Weldangrind]

That's good news. A larger slow jet would help it warm up faster, and they're cheap and easy to find on eBay.

[Jasonbber]

well I finally bit the bullet and ordered a new lifan 200 engine. The conversion of the 125 to 225 is not possible and last weekend I think I blew the rings on the 125 engine. I have no compression at all.
So rather than rebuild the 125 engine I figured I'd get a new 200 engine and put the 67mm jug and ported 250 head that I have on it.
I had to sell the TS185 to pay for it, but that's OK

I love what you have done to the panterra. So far you're the only person I have seen do a successful motor swap on here. Since you decided to go with a Cg200 and said that was the biggest thing the bike could fit, I went looking for suitable cg200s and came across a seller on taobao that has the dimensions of the cg200 and the Cg250 side by side and they have almost the same dimensions.

http://i61.tinypic.com/2i1grbr.jpg

Did you verify that a cg225/250 wouldn't fit? Thank you for your help! Great thread.

[Weldangrind]

There isn't likely to be much of an external difference. The displacement is all about bore and stroke, and the engines share the same frame of architecture, for the most part. An engine over 200 (like a 223) has a larger stud spacing for the cylinder, but even that doesn't make much difference. I've yet to see an actual air cooled 250; many of them are labeled as 250, but they are actually 223 or 230.