different shock and spring (thanks RK!), new rear tire, chain, ring and cog… broap!
[quote=“pommes king”]different shock and spring (thanks RK!), new rear tire, chain, ring and cog… broap!
[/quote]
That new?
I’d have said it looked a bit hooked. Must be the angle.
Then again, my rear chainwheel was terminally hooked, according to people who knew, and I thought it looked ok, so apparently I can’t tell the difference 
.
All new sprockets I’ve ever seen have flat tips on the periphery… that become hooked or pointed with wear. I’m pretty sure that’s the old sprocket in the pix, since one tip is broken off.
[quote=“Ducked”]
That new?[/quote]
On top, the chain (without halflink) was too long and the rear wheel in the most rear position, so would just jump. 
I definitly didn’t want to put a brandnew 3,5K chain on that thing anymore.
One other small ghetto-mod is the electricity wire-tube that I wrapped around brake hose and speedo cable - I hated the way they’ld bend when the fork went in before.
So that’s the before/knackered picture then.
Phew! I thought it looked pretty bad but I’m not super-confident of my judgement in this context.
And I was trying to be polite 
3.5k for a chain??? Must be something pretty fancy.
What you need (as well as a new chain and sprokets, of course) is an …Eds Oiler.
https://forumosa.com/taiwan/viewtopic.phpf=75&t=81769&hilit=eds+oiler&start=40#p1066350
Discussion of chains on there too
New “improved” models would be available, but I don’t really ride any more so havn’t been able to test them.
Tafcoml I thought your bike was a mk2 (small CPI logo on the clutch cover). They didn’t have the gearrbox probs I don’t think.
My CPi stopped again and wouldbn’t start forr a couple of months. Finally I got them to take it away and they changed the front brake presssure switch and the CDI. It cost about $2500 for the lot.
I’m selling iit on ruten now. It’s all cleaned up and ready too go to a good home. Wife’s scooter is dying and needs to be replaced. Hun do chen not forthcoming, so tthe CPI is covering that.
Hopefully get a KTM Duke 350 to replace it in 2-3 years, or an MX bike when George is 5.
Bye bye CPI. t’s been a pleasure.
Hi guys,
I’m living in Taipei and I’ve found a second hand CPI 250sm which I would like to buy. The problem is that I’m a newbie and i will be not sure if i buy a piece of junk or a good second hand bike. It would be awesome if some kind hearted bikers in Taipei would come with me to have a look at the bike. A nice meal at my place is offered to the kind hearted guy; I’m italian and i cook good pasta haha!
Thanks in advance
Filippo
Welcome Filippo. Do you know what year it was made? What price are they asking for it? Is it still standard or have they added anything extra?
Thanks for the answer: it is a 2010 bike and they ask 75.000 NTD for it. I don’t know if they added anything extra; is that a fair price?
I thought so too. Oh well shrug. Good luck with CPI sale and let us know what happens with that KTM.
Depends on condition, whether they’ve changed anything, etc. Why not message jaame - he’s selling his. I sure he’ll let you know what shape it’s in if you send him a pm. And if the scallywag swindles you, at least it’ll have been in a language you can understand 
[quote=“TaFCoML”]
Still in coms with CPI HQ and will update what their response is soon.[/quote]
Any news?
I just came back to TW, did 2 early morning rides and turned my front tire into a weird semi-slick
Battery died while I was gone, oil change is needed, maybe front brake pads & I still want to change my front light and footrests… apart from that, all is good. (so far)
1000k old:
good times:
They’re sticking to their guns that it is a maintenance error and avoided a hypothetical question (whether if proved to be a manufacturing issue they would fix it). They wanted me to put the bike back together and move it to one of their registered dealers before allowing the dialogue to go forward. If they’re not going to help with the repairs, I’d rather stick with a mechanic I know and who can speak English.
So far polite, but not helpful at all. I did hear from my mechanic, however, that CPI was selling him the parts needed for the repair at ‘a nice price’. Still waiting on the numbers, so no final word on this whole debacle yet.
Shweet pics btw. Where’s that mad bridge you’re going over?
They’re sticking to their guns that it is a maintenance error and avoided a hypothetical question (whether if proved to be a manufacturing issue they would fix it). They wanted me to put the bike back together and move it to one of their registered dealers before allowing the dialogue to go forward. If they’re not going to help with the repairs, I’d rather stick with a mechanic I know and who can speak English.
So far polite, but not helpful at all. I did hear from my mechanic, however, that CPI was selling him the parts needed for the repair at ‘a nice price’. Still waiting on the numbers, so no final word on this whole debacle yet.
[/quote]
As I understand it, CPI’s position is that the failure was due to your black hand not cleaning the oil strainer. Correct?
My motorcycle experience is limited to a Honda SS50 many years ago in the UK (which I never took apart), a couple of RZR’s (no filter) and a Zing here.
If the CPI engine is like the Zing (a Honda CG125 copy) its got a rather crude wire mesh screen and (IIRC) a centrifugal one, which I never cleaned. The filter was a REAL bastard to get to, since the cover on mine was very difficult to get off, so I’d guess its quite possible that a black hand wouldn’t do it routinely.
On the other hand, I doubt that screen blockage would prevent oil flow, since I assume (perhaps incorrectly) that there is a bypass path, like on a car.
Can someone who knows this engine (or motorcycle engines in general) confirm this point, which seems to be critical in context?
Since the engine is in the (black) hands of the guy accused of breaking it, any evidence may be compromised or gone.
Have you seen the state of the oil strainer?
IF there was load of crap on it, that’s still not necessarily the cause. It could be an effect rather than a cause of your problem, and, 4WIW, that’s the way I’d bet. These engines have a reported history of gearbox problems.
Unfiltered oil is the norm on motorcycles and shouldn’t itself be fatal provided the oil is changed regularly and it continues to circulate.
It seems slightly unlikely that oil starvation would cause a failure to change gear, (which I understood was one of your symptoms) since gearbox stuff is at the bottom of the engine and I don’t believe it is normally pressure lubricated.
If a crankshaft or big end bearing failed (we still don’t know what the specific problem is) that would be consistent with oil starvation.
Update 3:
Yes, I believe that is what they’re saying. From the attitude I get from some of the mechanics at the bike store I frequent, it’s not impossible that corners were cut whenever I asked for a servicing. I did regularly (every 1000km) change the oil though. All in all, I’m not too chuffed with the quality of either party’s product (I feel I should add however that CPI corresponded in a professional [and most importantly, English] manner throughout). Final price-tag: NT$25’000.
Some expert opinion/info from the UK-based Visordown site:-
"My CB250RS honda had a gauze strainer type filter. It was well known that if this got blocked then it would starve the head of oil and lunch it fairly quickly. That said, those engines (and the massively similar XL250) used to lunch their top ends fairly quickly.
I don’t recall my 250RS having a bypass valve. Bypass valves are used on full flow oil filters being used on the high-pressure side of the oil pump. Given the construction & sealing of those gause oil filters I’d be surprised if they’re either full flow or on the pressure side of the pump.
The gearbox won’t have pressure-fed bearings, but probably uses jets of oil directed to the right places - most seem to do this.
Similarly, I think the crank and big-end on those 250RS hondas were all roller bearing rather than pressure fed plain bearings."
"Well if those forum pictures are anything to go by then it ain’t a direct copy of the XL250 / CB250RS engines - they were single cam, 4 valve with bifurcating rocker arms. I do recall an unpopular CBX250 however - I believe that was very, very similar but with twin cam head so could be based on that?
The bottom end looks pretty similar tho’ - balance shaft, gear shafts & shift mechanism all in the same place. Might be an XL250 with an updated cylinder head for emissions purposes?
Those cams are indeed scored, along with their bearings. That was a common problem with all those engines, made worse by them running directly in the head. In theory you had to junk the whole lot, but many engineering outfits developed ways of re-bushing the heads.
The principal reason for the frequency of the bearings scoring was generally accepted as people not bothering to clean the oil filter gauze. On the single cam engines the rocker shaft seals used to leak too, sometimes so much that people just kept topping the oil up rather than changing it. That was pretty bad news too!
Only way to know what’s caused your friend’s engine failure is to strip the engine, find the principle damage and then assess that. You can tell all sorts of things from fracture sites, bearing surfaces etc if you know what to look for."
Read more: visordown.com/forum/workshop … z26VFYQdmb
Read more: visordown.com/forum/workshop … z26VFLPwsC
I think that stinks. Clearly CPI have some issues with engines breaking. I’ve seen you ride, you’re not the kind of guy that murders bikes. They should do the right thing and sort it out FOC, no question about it.
I’ve had a few people asking about mine but they all want to pay half now, half later (!). As if!
Some shots of mine:
New shoes by Photos By 夏天, on Flickr
Taking a Break by Photos By 夏天, on Flickr
Stopped by Photos By 夏天, on Flickr
Fresh Meat by Photos By 夏天, on Flickr
CPI SM250 by Photos By 夏天, on Flickr
2 of 3 beep beeps by Photos By 夏天, on Flickr
tdp, any mods other than brake calipers, rotors, and chain?