|
Post by cerberus73 on Feb 12, 2011 22:12:55 GMT
ok guys i picked up a baotian BT110-2 stepthrough, bikes a 2008 model, 271 kilometers on clock, 5 speed semi auto box... was a relatives first bike, they dropped it on a roundabout at low speed, busted most the left side front plastics, priced up the parts from the importer... scary! 180 quid plus 90 for an exhaust... suffice to say i only bought the thing for the engine really, plan was either, fix it up and run for a yr as a hack, or if i couldn't get parts at price i was willing to pay, drop engine n use it in my cub... after suitable modification of course (read that as more power!) i am waiting on a call back from a breakers down south that may have the plastics, but if not... i need info on what i can or cannot do to this engine... ive virtually zero experience of chinese pit bike type engines, but am familiar with the old C90 ones.
Are all these chinese C90 type engines the same, are parts interchangeable? ie are all the castings made from one set of patterns, then various parts just assembled and branded under diff names, or are they visually similar but parts not interchangeable? cos basically i would like to fit a slightly hotter cam, stronger valve and clutch springs, big valve head, and stronger clutch plates, and a manual clutch. and ill have basically a brand new reliable and slightly more pokey engine for my cub, after the other work im doing to her, she will be almost as good as a new bike...or thats the plan, i want reliability over sheer speed more than anything, but if i can get a few mph over the standard cubs 50-55 i wont complain to much (65 mph would be nice!)
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 12, 2011 23:53:38 GMT
Ive also got a 110cc chinky engine.
I havent heared of a 5 speed semi, mines a 4 speed semi.
The casings are usualy the same, but im not 100% as yours is a newer 08 modle. Im sure there is a factory were they are all produced, then flogged off to the many pit bike companys were they put it onto their fancy frames ect.
You will be able to fit a hotter cam, all the heads are the same, so will the valve springs. Big valve head for any 110cc pit bike engine will it.
TBH, i wouldnt bother with a manual conversion. With a semi, you can just chuck it into gear, and if you keep the throttle on, you will wheelie from 2nd into 3rd, once I even got some lift into 4th. Probably upgrade the plates and springs, but havent seen them for sale. Im guessing its 5 up/down gear pattern? No more faulse neutrols ;D Bit of fun at the lights, pop it into 2nd, but keep your foot pressing the changer, this way its in neutrol, give it the beans throttle, then let your foot off, you will fly!!!
If I were you, fit a upgraded head, carb, manifold, keep it semi and have some fun. That way youve got a reliable bottom end semi, and very good throttle responce with the opened up top end.
|
|
|
Post by cerberus73 on Feb 13, 2011 0:02:59 GMT
cheers derek, aye its a 5 speeder all down like the cub, Neutral, 1-2-3-4-5 to be honest i prefer the control a manual clutch gives, and its easy enough to pick up a "parking brake" lever off a old C50 automatic to use as a clutch lever. if i could find a decent 125cc barrel and big valve head id fit that with uprated clutch and a oil cooler, 22 or 24mm mikumi carb with a proper K&N and the right jetting. i dunno yet about changing the sprockets for better uphill ability, or acceleration, 16t or 17t front and one less on rear, i know gear lever will need to change cos its made for bloody bigfoot! no way u can heel n toe it up and down the box... ive only wee feet for a big guy, need size 14s for it not 8s! prob just use a cub one and kickstart on it, im guessing it will need a non-standard exhaust as well.
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 13, 2011 0:27:54 GMT
|
|
|
Post by TerraRoot on Feb 13, 2011 9:38:36 GMT
worth poping the head off to check what valves sizes you have, dratv.com has plenty of info on it and is quite cheap for performance bits should be two different types of cam. Check your gearbox again, are you counting neutral or something? i can only find aftermarket 5 and 6 speed conversions, no standard ones also if it's electric start it might not fit the honda frame, if the honda frame is quite old it just might need a bit of a trim to the frame and it might slip in, need pics really.
|
|
|
Post by cerberus73 on Feb 13, 2011 10:12:50 GMT
lol derek i only paid 120 for this complete bike and already sold the frame and other parts for most of that price. so engines basically costing me not much at all, so a extra 50-60 on heavy duty parts aint gonna break the bank. and still works out cheaper than a complete standard 125, i also love to mess about with stuff, great learning experience. and satisfaction when you have done it yourself. rather than a off the peg go faster unit.
it may be a 4 speed, i will need to check further, but they relly i bought it off assured me its a 5 speed, but i only ever had her up as far as 3rd when i took it for a test run. i need to drop the engine out and check to see what kinda cams i have, other reason i wanna fettle this engine is that it was built with a decent road going electrical system, enough to drive lights etc, as i know some pit bike engines only really produce enough juice for ignition, not enough to drive a full set of lights etc. its a kick start only engine, no electric boot. and its a 1994 square headlight 12V Cub 90, so engine should drop in with no modding to engine mounts, and as it already has the correct manifold to mount the carb in the correct "cub type" position then should be a easy fit... only thing will be marrying up the electrics, hopefully these are identical to a standard cub regarding number of wires etc.
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 13, 2011 11:31:18 GMT
Wiring should be easy enough. There will be either 5 bullet connectors or a plug with the wires in there. If they are both different, thats when the fun happens! But its always 5 wires.
If that happens then you will need the wiring diagram fromm the donar bike, then match up the wires to the cub loom, the wires will be different colours no doubt.
|
|
|
Post by cerberus73 on Feb 13, 2011 13:36:08 GMT
5 wires sounds simple enough its when you end up with plastic coated spaghetti in nice big bunches that it gets dodgy! cheers for the info guys. its most helpful, keep it coming!
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 13, 2011 14:42:17 GMT
Let me know if you need any help, ive done quite a few pit bike stator plates and wiring.
|
|
|
Post by cerberus73 on Feb 13, 2011 15:31:25 GMT
will do derek cheers muchly!
|
|
|
Post by cerberus73 on Feb 15, 2011 20:26:02 GMT
right derek or anyone else knowledgeable in such things... i have went and stripped that engine out of that chinese honda cub/innova knock off today, turns out my young relly was telling fibs, the bike IS electric start, and he had busted a exhaust stud at some point, as well as at some point taking the engine out of the bike (it had half the mounting bolts missing already!!! eek i had driven this thing no wonder it felt unsafe, it was barely held together! harsh words shall ensue when i see him next! right onto the point i will post some pics first so you can see what im twittering on about. and the busted stud! right derek you said that pit bike engines have 5 wires, right this bike has 4 in a block connector and a single one with a bullet type connector coming out of the mag/generator side, these are pretty thick wires, and near the sprocket there is another cable with a block connector with 6 terminals but only with 5 wires entering it any ideas? the electric starter is driven by 2 wires that are at moment still attached to the wiring harness of the donor bike, i now need to figure out how to get this to marry up to my c90... im thinking i need a new wiring harness off a later model electric start c90, and the switchgear with start button etc on it. but Q is what wires will go where! im a bit stumped, the stud is an easy fix, getting it done this week for 20 quid, and 2 new studs fitted.
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 15, 2011 23:20:23 GMT
Ah some nice pictures to get my eyes into ;D
The wee round black thing by the sprocket is to do with the neutrol position switch, you can actually change gear by putting a socket on the nut inside, so if your c90 harness has that wire/plug then that will be and easy match, if it doesnt then you can remove the black penny thing and the wires.
The main wires that come from inside the generator cover power your lights and all that, the single bullet connector could be an earth. Is the c90 a plug type or 5 connectors? Do you still have the bike it came from?
Do you still want an electric start? I made a blanking plate for mine were the motor went. Yes you would need the later electric start loom.
It does sound and probably look complicated, but at the end of the day, forgetting the electric start and neutrol position switch, its 5 wires. If you could get a wiring diagram for the donar bike that would be great.
I could come round this weekend if you need.
|
|
|
Post by cerberus73 on Feb 16, 2011 0:00:27 GMT
at moment im getting the cylinder drilled to remove that busted stud at breaking point tomorrow, i did think of just getting a blanking plate and doing away with electric start.
a guy on the C90 club forums has explained the connectors and where they go on a cub... he has done a few of these engine swaps, lifans, xy's, wuyangs, im trying to get him to help regarding wiring on the cub so i dont have to butcher my loom or need a completely new loom, he has drawn me a nice diagram to follow as well for when i do wire it into my cub, what im gonna do is check my c90, see what connectors it uses and get some and replace the ones on engine with cub type so just push together. i would like just a push button in a hidden location so my cub still looks standard.
i wont be changing this engine over till i work out what go faster goodies i can plonk on it, and i rebuild the clutch with heavy springs, and plates.the engine in my cub is good at moment, this engine will be rebuilt with uprated everything for reliability, and a bit extra poke. i would love a hand rebuilding it once i have got a hotter cam, a proper 22mm mikumi, not the 19mm mikumi copy on it at moment, some heavy valve springs and possibly a big valve head. high comp piston, i want my cub to be good for 60-65 mph and 120 mpg but still look standard and use standard exhaust etc. so only a 110cc engine allows this, a 125+ means using a pit bike exhaust modified so people will know it aint a standard cub. id like an engine i could really depend on, that wont crap it innards all over the road after a couple of hundred miles, but with a bit more go on the flat and pulling power on hills.
|
|
derek
Retro Apprentice
Posts: 75
|
Post by derek on Feb 16, 2011 7:25:35 GMT
|
|
|
Post by cerberus73 on Feb 17, 2011 18:39:39 GMT
i gave them a bell but the guy i need to bend the lughole off at ooracing wont be in till the morn, so i will be giving him a call for some advice on what will/wont work regarding tuning, im thinking maybe some polishing of the intake/exhaust ports just to smooth off the casting roughness, nothing drastic, and possibly a big valve head and higher comp piston. will also ask him about manual clutch conversion and heavy duty clutch bits. and need to look for a mikumi 22mm carb and suitable jetting for a K&N filter. then after that ill need to take advice form the c90 club guys regarding sprocketing, what will give balance between acceleration and hill climbing ability.
|
|