What Engine is This?
Moderator: rztom
- T.RexRacing
- Posts: 1318
- Joined: Fri Nov 01, 2013 8:34 pm
- Location: back in the hills
Re: What Engine is This?
Capable? Absolutely. Out of the box? Nope. Mid 50s out of the box and an easy 60+ w/o suffering reliability. Beyond that and they become race bikes and not very suitable for riding. How do I know? For starters dyno tuning has paid my bills since the early '90s. Granted most of my work is with Harley and big I4s but I've tuned everything from Z50 Hondas to Ducati D16RR.
Since we're allowing stuff found online. Click me
Below is what the bike had to get to 60HP. Look at the article and see what it took for him to get 90 HP. Notice the 90HP runs BEGIN @9300RPM. This is a heavily modded motorcycle not close to what Honda supplied.
1) Crankshaft aligned to within 0.01mm tolerance
2) Flowed rear upper crankcase and added material to get TDC crankcase volume equal (593ml).
3) Cleaned up transfer port lip edges on barrels to give better flow.
4) Installed 15% lighter Wossner pistons (for 2003 RM125) with 2 holes for exhaust port bridge cooling/lube.
4a) With deck height of RM125 pistons being 0.6mm less than standard, this effectively lifts all ports by 0.6mm or 2.4 degrees at top of exhaust port.
5) Machined heads for 0.8mm squish and 12.8ml combustion chamber volume. Standard is 1.1mm and 13.3ml
6) Installed Mototassinari V-Force III reed blocks.
Since we're allowing stuff found online. Click me
Below is what the bike had to get to 60HP. Look at the article and see what it took for him to get 90 HP. Notice the 90HP runs BEGIN @9300RPM. This is a heavily modded motorcycle not close to what Honda supplied.
1) Crankshaft aligned to within 0.01mm tolerance
2) Flowed rear upper crankcase and added material to get TDC crankcase volume equal (593ml).
3) Cleaned up transfer port lip edges on barrels to give better flow.
4) Installed 15% lighter Wossner pistons (for 2003 RM125) with 2 holes for exhaust port bridge cooling/lube.
4a) With deck height of RM125 pistons being 0.6mm less than standard, this effectively lifts all ports by 0.6mm or 2.4 degrees at top of exhaust port.
5) Machined heads for 0.8mm squish and 12.8ml combustion chamber volume. Standard is 1.1mm and 13.3ml
6) Installed Mototassinari V-Force III reed blocks.
There is only one difference between a madman and me. The madman thinks he is sane. I know I am mad.
Salvador Dali
Salvador Dali
Re: What Engine is This?
Wow.
Sounds like that little rat bike might be faster than most RZ350s.
I didn't expect that at all. I just couldn't identify the engine and was curious.
Sounds like that little rat bike might be faster than most RZ350s.
I didn't expect that at all. I just couldn't identify the engine and was curious.
Re: What Engine is This?
Faster? Yeah, if the challenge is "who pukes first" or maybe as long as the road does not have any corners.
Man that pile of crap is a crime qualifying you for death row.
I just imagine the rider as one of those bearded hipsters trying to look like a logger.
(Not that filthy smelly ones but the ones trying to impress other loggers).
Man that pile of crap is a crime qualifying you for death row.
I just imagine the rider as one of those bearded hipsters trying to look like a logger.
(Not that filthy smelly ones but the ones trying to impress other loggers).
Bye
Martin
Martin
Re: What Engine is This?
MK wrote: I just imagine the rider as one of those bearded hipsters trying to look like a logger.
(Not that filthy smelly ones but the ones trying to impress other loggers).
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid
Like Watches? www.PloProf.com & www.DeskDivers.com
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid
Like Watches? www.PloProf.com & www.DeskDivers.com
- Questo vecchio rz
- Posts: 1116
- Joined: Sun Aug 16, 2015 5:55 pm
- Location: Reconquista of California
Re: What Engine is This?
Most average NSR250s fall into the 40 h.p. range, especially versions that were not derestricted. MC16-21s progressively gaining better, then at the end Hondas crown jewel obviously the MC28. Arguably the finest example of any 2 stroke street bike ever produced by any manufacturer.
Wet clutch, is standard on many models then typically SP variants gain a dry clutch.
Alot if work, went into that...Whomever has it likes it, but for me...it's all over the styling map..Po l'il bike has a identity crisis doesn't know what it wants to be.... retro, modern, bobber, cafe..
Wet clutch, is standard on many models then typically SP variants gain a dry clutch.
Alot if work, went into that...Whomever has it likes it, but for me...it's all over the styling map..Po l'il bike has a identity crisis doesn't know what it wants to be.... retro, modern, bobber, cafe..
Last edited by Questo vecchio rz on Sat Feb 17, 2018 11:53 am, edited 1 time in total.
Banshee (Baja) race bike,+ 2 A Arms,L.E.Ds, Toomey, +4 stroker IMS tank, run flats.
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500
Re: What Engine is This?
That's what I love about this place.MK wrote:Man that pile of crap is a crime qualifying you for death row.
You guys keep me from doing stupid shit with my bikes.
Well... at least unsafe shit!
Re: What Engine is This?
You're right there. That puppy is extremely dangerous to ride.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine
Re: What Engine is This?
The moment on that second caliper shows who ever built this thing is an idiot.
Re: What Engine is This?
The last (designed) true street based 250 was the Suzuki VJ23.....Not Aprilia....built for 7 months in 1996...
The Aprilia RS used the older Suzuki VJ22 engine as a base....Suzuki did all the head/cylinder casting also...even though the engine had Aprilia written all over it.
Yes, the bike pictured is a NSR engine, never sold outside of Japan new so 45Hp would have been the max originally.
The 250 class GP race bikes were another story all together
The Aprilia RS used the older Suzuki VJ22 engine as a base....Suzuki did all the head/cylinder casting also...even though the engine had Aprilia written all over it.
Yes, the bike pictured is a NSR engine, never sold outside of Japan new so 45Hp would have been the max originally.
The 250 class GP race bikes were another story all together
73 TS/TM400 Supermoto
78 GS1000E
80 KD80
82 Katana
84 RZ350
84 RZV500R
86 GSXR1100
86 1100 sportster
88 FZR1000
89 RGV250SP VJ21
90 RGV250SP VJ22 FL
91 TZR250SP 3XV2
96 RGV250SP VJ23 T
99 RS250
02 Hayabusa
16 KTM 390 Duke
17 KTM 1290 SDGT
21 RSV4 1100
78 GS1000E
80 KD80
82 Katana
84 RZ350
84 RZV500R
86 GSXR1100
86 1100 sportster
88 FZR1000
89 RGV250SP VJ21
90 RGV250SP VJ22 FL
91 TZR250SP 3XV2
96 RGV250SP VJ23 T
99 RS250
02 Hayabusa
16 KTM 390 Duke
17 KTM 1290 SDGT
21 RSV4 1100
Re: What Engine is This?
Pretty sure I said it right.Smoker wrote:Holy shit.
I was thinking NS250R engine, but doesn't look right.
I was also thinking NSR250 engine, but a factory race engine?
The bike engine looks like a wet clutch, but the power valve system is a match for the NSR250. Probably a hard cover over the dry clutch.
If that's an NSR250 engine, there's your answer for front dual calipers!
Isn't the NSR250 a factory race bike, and the NS250/NS250R are production bikes?
- Questo vecchio rz
- Posts: 1116
- Joined: Sun Aug 16, 2015 5:55 pm
- Location: Reconquista of California
Re: What Engine is This?
Honda is a little all over the map, with model designations. RS, NS, NSR, NR etc...
Honda "production race bikes" were RS250s, the street bikes MC 16/18/21 & 28s were known as NSR250s.
Many "Factory Works" race bikes were also labeled NSRs.
A "production race bike" RS250 is significantly faster than a production street bike NSR250, Then you go to the "factory" 250s and there again that Xtra bit of performance
Honda "production race bikes" were RS250s, the street bikes MC 16/18/21 & 28s were known as NSR250s.
Many "Factory Works" race bikes were also labeled NSRs.
A "production race bike" RS250 is significantly faster than a production street bike NSR250, Then you go to the "factory" 250s and there again that Xtra bit of performance
Banshee (Baja) race bike,+ 2 A Arms,L.E.Ds, Toomey, +4 stroker IMS tank, run flats.
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500