Yamahdan Posted March 21, 2013 Posted March 21, 2013 Hi all, I have a couple of queries and was hoping some bright sparks on here might give me the info... I have been looking at YZ 125's, mainly the engine, and I know there are differences but I was just wondering if anybody knew what the main differences between them are that give the yz its extra umph, I mean is it as simple as porting differences or is it a completely different engine?? Exhaust and carburettor are a lot bigger and gear ratios must be different for the track use but what about the engine internals?? They have similarities in look but this doesnt mean anything.. Any help appreciated, I guess everyone can tell what I'm thinking about doing... Thanks Danny 1
busyeddie Posted March 21, 2013 Posted March 21, 2013 Woah, thats a very open ended question. What years? A 1978 dt is very different to a 2006 yz
Moderator Airhead Posted March 21, 2013 Moderator Posted March 21, 2013 its another how do I bolt on another 20bhp question
Moderator Cynic Posted March 21, 2013 Moderator Posted March 21, 2013 Its an old question that turns up every so often. In truth the IT series is closer to dts but its still a long way from a yz. Service intervals and piston life are measured in hours. A modern yz is kicking 40 odd totally uncompromising psychotic horses. The only real link is the cc and the name on the cases.
blackhat250 Posted March 21, 2013 Posted March 21, 2013 Have you ever ridden YZ125 Dan" there is no bottom end at all, Clutch slipping take offs are a must, this is caused by raised exhaust ports, That why a powervalve is a godsend on road two-strokes. valve is closed so you get bottom end torque, and when it opens " Its Yahoo " The exhaust on the Yz will be a real expansion pipe , The carb is bigger, and bigger reed block,
dt502001 Posted March 21, 2013 Posted March 21, 2013 You will spend more cash on parts than gas monthly,and be tearing it apart every week if you drove it daily.for ring replacement +full service. Thats why when you see a dirt bike for sal something like "4hrs on new top end" will be in the add.
busyeddie Posted March 21, 2013 Posted March 21, 2013 That said theres nothing stopping you putting a yz engine in a dt. if you do your homework and get the right one they bolt straight in. But with more horses, on the more modern yz's at least, you get better suspension than on a dt.
Moderator Airhead Posted March 21, 2013 Moderator Posted March 21, 2013 That said theres nothing stopping you putting a yz engine in a dt. if you do your homework and get the right one they bolt straight in. But with more horses, on the more modern yz's at least, you get better suspension than on a dt. how about L plate restrictions and insurance company notification ed...Its just a dream IMO
kenDAWG Posted March 22, 2013 Posted March 22, 2013 It's not a dream if its doable who says once full test is passed said person likes his little dt but would like it to have a little more gallop and has access to a yz engine? I can get a yz engine for mine but I haven't passed my test and I'm not competent enough to do it myself. Ken
Moderator Airhead Posted March 22, 2013 Moderator Posted March 22, 2013 not worth it ken, the insurance would be huge
busyeddie Posted March 22, 2013 Posted March 22, 2013 I know what your saying Paul. Thats for yamadan to worry about. Anything is possible, whether it's worth it is a matter of opinion. I'm tempted to put a yz 125 engine in a dt mx frame ive got,
busyeddie Posted March 22, 2013 Posted March 22, 2013 Tell the dvla ive changed the engine number. And use it for enduros. Its a 125 frame too...
Moderator Cynic Posted March 22, 2013 Moderator Posted March 22, 2013 Be easier to buy a complete yz and get a daylight mot. They sell for peanuts once there not competitive anymore.
busyeddie Posted March 23, 2013 Posted March 23, 2013 I'm thinking 77 -78 aircooled yz though, with the chain in the right place. Theyre a bit pricey, plus I.have the bits to do it. The other option is either a yamaha blaster engine in one of my 175 frames, or an rt180. But I'm not convinced the rt would be worth the aggro.
kenDAWG Posted March 23, 2013 Posted March 23, 2013 Hmmm I'm looking at a road reg yz on eBay now!!! Got me thinking now Ken 1
Yamahdan Posted April 2, 2013 Author Posted April 2, 2013 Thanks to all for the replies, I am not actually interested in putting a yz engine in my bike nor am I looking for the bolt on 20hp, I was thinking more around the porting side along with the carb and the exhaust, which would be moderatly easy fits. I already have the exhaust which I am working on, may take some jiggling but its looking promising at the moment, but I'm fussy with looks and if it don't look right its getting binned. I'm going to be using the DT for enduro's as well as a daily ride so I'm just trying to find a happy balance between power, reliability and cost effectiveness.
kenDAWG Posted April 3, 2013 Posted April 3, 2013 Well to be honest carbon reeds, full after market exhaust and a professional setup of the carb is all you want. The dt is setup for reliability so one you start with the tuning them the reliability will suffer!!! There is a dt125re with yz125 engine in on eBay now £1600
Moderator Cynic Posted April 3, 2013 Moderator Posted April 3, 2013 I'm going to be using the DT for enduro's as well as a daily ride so I'm just trying to find a happy balance between power, reliability and cost effectiveness. Thats unlikely. I have built vehicles to try and bridge that gap and it dont work. You have something that is average at both at best. It will be weak on the track and frustrating on the road.
kenDAWG Posted April 3, 2013 Posted April 3, 2013 I've got my dt so its up to 60mph in no time for on the roads its a little bit scetchy with the mich ac10 tyres but on the green lanes its perfect I am currently thinking about some spare wheels with road tyres on!! I don't think there is ever going to be a bike that is perfect on and offroad its just something we have to admit.. I had my dt out with a mate on his yz125 and he just left me behind blasting about but at the end of the day he was waiting for his father with trailer to pick him up but I just went on my way. Ken
Yamahdan Posted April 9, 2013 Author Posted April 9, 2013 I would rather have something that is a bit better off road because I use byways and country lanes to get to work and the longest bit of "normal" road I use is all up hill and about a mile long, all the rest is running up and down the box and rev range so I want something thats a bit "twitchy" on road and mediocre off it. Getting to-and-fro the enduro's may be a bit different but this will be once in a while so not that important. We will see, I suppose it's going to be trial and error... Thanks, Danny
Recommended Posts