Kp-Mini Self-Destruction [Build]

[Falkon45]

I'm loving the outcome of this!!!

[deadwood83]

This is the question we all want to know.



Until now, nobody was sure. All we knew was:

• CRF150/230-based engine.
• Kinda looks like a Z125 if you squint really hard and take off the tailpiece
• Embraces the recent 'My motorcycle is an insect' trend.

But what is that frame? What is it? Why do there seem to be no drop-in shocks? What do I do if I need stem bearings? Does every mod to this bike need to be custom made? These are the important questions.


I started by looking at the suspension. I think the tail end is too low. I would say I range from a bear of a person to a whale of a person depending on how recently I have had a haircut. So a rear lift is in order to fight my natural booty sag.


A gentleman by the name of Mike Davis posted some months back in the KP Mini group about drilling out the rear linkages to raise the rear end, but the more I looked at it, the more it seemed that shortening the lower linkage just broke the geometry of the bike. Sure, it effectively lifted the rear and increased the preload, but it seemed like a band-aid for a poor design.

THis was reinforced when I took some snapshots of the bottom of the suspension geometry, the did some CAD after scanning and measuring the cush linkage.


Why is the suspension alignment in the rear so wonky? Why is lifan taking a simple triangular part and translating a simple force vector in the ZY plane cross multiple ZY planes in the XYZ coordinate space? All the Japanese and European monoshock bikes with symmetrical swingarms are keeping their linkages symmetrical, and even the 150cc bikes from the big four have a full motor cage/cradle. Why does the rear suspension linkage look so half-baked? The swingarm pivot is centered, the frame mount is centered, so why is everything else looking so skewed and why did they cast THREE different offsets into the cush pivot? What is this?


Enter; The Googles.
Oh I see. I see now. It's an XR100/CRF100 hybrid with a chopped XR200 front frame tube. We must go back to basics in order to understand why they did this.

1. Castings/molds are expensive
2. R&D is expensive
3. People are expensive.

So if I were Lifan, how would I cut costs and maximize profit to keep the Chinese government happy and push the rhetoric of 5 year economic plans?

• Build to a standard that is cheap, and is strong enough to outcompete other Chinese minis while being weak enough to keep customers replacing bikes.
  
  • Copy a frame that is known to bend long-term with abusive riding, but put in a small enough powerplant to prevent this from being obvious
  • Remove the lower frame cradle from the XR200 front setup copied off of older bikes to keep assembly cheap. If a machine/lift can place the engine, then workers need to be less fit, less skilled, and less well-insured while minimizing workplace injury risks.
  • Old Japanese tooling can be copied and design examples are plentiful. R&D is cheaper if we don;t have to do much of it at all.
• Minimize costs by reusing parts that exist. This was reinforced in my first engineering design class. "If somebody already makes it, do not reinvent it, that makes you less valuable since your efforts hurt the bottom line."
• Cut corners where they won't impact the overall perception of quality, and won't be noticed as a major failing.
  
  • This is the rear linkage in a nutshell. Look at the photo above of the Honda XR80/XR100/CRF100 linkage. It is a cast piece (expensive). It was cast so that Honda could mold in the offset of one of the legs in a repeatable fashion rather than build out a whole series of tooling to press/forge a single bend. This means that for an initial expense (molds and process) they can reduce the number of rejected parts due to metal fatigue and machine wear on the bending/forging of the part.
    
  • Lifan decided that (from what I can tell):
    • We will already be casting one piece (the cush linkage)
    • We can add offsets to the linkage to compensate for offsets in the previously cast piece.
    • Assembly costs and failure rates can be cut down by having two loose hoop bars over a steel tube which is welded together in a cheap jig.
    • By utilizing sliding through-bearings in the cush linkage, assembly precision will be less critical because slop will be designed in, and opposite tolerance stacking will take care of the rest.
    • Cut steel tubing/plate/cast parts oversize so as to avoid using custom length bearings and eliminate the cost and time of assembling bearings with wipers and endcaps.
      
  • Only body parts, seat, rear brake lever, swingarm (sort of? just mount the grom pivot on the bottom) are unique to the KP mini. Tail (subframe) is altered from the XR series but I am fully confident if I were to dig deep enough into the XR lineup of the mid eighties, I could find a matching subframe that Lifan copied.
    

Lifan is not stupid, and their engineers are not stupid. They achieved their goals, but the end product is not quite as premium as the initial inspection or curbside-analysis would have you believe. For most people, they would probably not notice or care about this. I wanted to tweak the suspension, and I wanted to do it right. I wanted to prevent my frame from bending at the headstock.



Implications of the frame basis discovery:

1. The XR200 frame accepts the same motor layout and mounting as employed by Lifan. Since the frame is mostly built around the XR100/XR200, almost no engineering work is required. People have even swapped lifan 200CC engines into the XR200.
2. The suspension setup is nearly 40 years old.
3. Aftermarket shock options without wonky workarounds! https://tboltusa.com/.../tbparts-dnm-rear-shock-for-honda... // https://www.vonkat.us/shop/100x-shock
4. Lifting links! https://rhmotoworx.com/product/rear-links/ (will also require the CRF100/XR80 wishbone/lower linkage, and potentially gentle bending if your lower linkage is as f**cked as mine came from factory). I have a full CRF150 wishbone+"cush link" en route.
5. If you stunt a lot, expect the frame to either flex or the rear top engine case mount to break.
6. The geometry of the default KP mini rear suspension is GARBAGE.
7. Lifan compromised the frame by removing the lower engine cradle. With cradle, old XR200s are still kicking even after 30+ years of jumping, trail riding, tree-crashing.
   

Here is an image of bottom-up on the KP mini compared to top-down on the XR100. Note the overall suspension geometry is nearly identical, with the Lifan having a wider lower linkage and malformed cush linkage to avoid paying to cast more parts. I pulled all bolts from the rear suspension and compared to parts on CMSNL, and the fastener specs are identical between the CRF100 and the KP-Mini.

https://www.cmsnl.com/honda-crf100f-...w#.YAzduhZlDUQ


The fix:

• I have ordered a CRF100 rear linkage set. If this drops in (which it should) then I can use one of the pre-made rear linkage lifts to preserve proper suspension geometry (keep some linearity of the rear shock travel in motion).
• I have ordered an XR200 frame without paperwork. The price was right, and I can cut out the bottom and have it welded to the KP frame. This will be cheaper than paying somebody to fabricate and weld a while new cradle system. I have neither tube bender, notcher, nor welder.
  

[franque]

Are you planning on bracing/gusseting the headstock?

Great info, love the research, it reminds me of the thread I made on here about the clutch covers, though yours is a bit more pertinent

[deadwood83]

Originally Posted by franque

Are you planning on bracing/gusseting the headstock?

Great info, love the research, it reminds me of the thread I made on here about the clutch covers, though yours is a bit more pertinent

Nah, headstock is fine after the full cradle is welded in. YOu then have three stress members connecting the headstock to the 'core' of the frame structure and have better used the engine as another stress member since it is now connected to the complete cradle. If I were putting MX suspension and planning to jump it super high then it would be an issue, but it's a street bike.


Also, RAD MOUNTS ARE GETTING MADE.


Huge thanks to SendCutSend.com. They offer laser cutting AND bending from your DXF files. Their bend calculators also supply K-Factor for your selected material .


Going full cradle was what really made this type of mount easy and possible. With the factory setup, I wanted to avoid drilling at the brace area at all costs. With full cradle, footpeg weight is taken off the engine (moved to cradle) and the cradle translates most of the forces at the crossmember-to-downtube point onto compression forces rather than tension forces. Adding steel rivnuts there now becomes no big deal at all.



Huzzah!




In other news, I realized I am missing a MASSIVELY important bearing!
The 5 speed transmission (which has a kickstart and is currently preinstalled into the engine) uses the standard clotch boss/bearing.gear through a 6006 bearing. (55mm OD, 30mm ID, 13mm thick). The 6 speed transmission omits this boss/gear combo because the extra space from the kickstart is necessary to ensure adequate gear thickness.




There is NO STANDARD BEARING that has a 55mm OD and 20mm ID (the shaft thickness). It also seems like having a mainshaft flopping around all willy-nilly might be bad for engine longevity. SO I put on my Sherlock Holmes hat and cloak.

• Tianda uses the 6 speed transmission, so something must exist, whether that is a different engine case, bearing spacer, etc.
• The Tianda parts fiche is just a ripoff of the Zongshen 5 speed parts fiche, so it has nothing relevant.
• SV Racing was way less than helpful once I revealed that I didn't own a Tianda, and just wanted to buy parts. The owner wholesale ignored me after that revelation.
• Attempts to reach Tianda directly in the past also resulted in being ignored.
• Zongshen told me in no uncertain terms to "please not contact us for individual requests."

Hmmmm........


Ah! But the CRF230L 6-speed shift star fit. I know their transmission is 100% not compatible, but I also know they do not use a kick starter. Let's see what the engine case looks like.



Um. Okay. That is interesting. That hole looks way less than 30mm. I can't use the retainer because the gear against the bearing on the zongshen is rather large, and would potentially hit the retainer's raised edges. But what size is this? How close is it really?



Oh. And that bearing? I need a part number.

BEARING, RADIAL BALL (20X55X11)
91005-KCN-003

The zongshen bearing sits proud of the cases. The honda bearing may not. I am hoping the tolerances will work themselves out, but if they do not I can always steal 1-2 of the flat washers from the 5 speed gearbox which no longer has a home.

ANOTHER VICTORY!


OH SNAP! A surprise and unplanned update! While typing this up, the XR200 frame arrived. Cloneluminati, confirmed. That cradle addition should be cake.

[franque]

Great stuff, I'm excited to see how this build is coming together!

While you've got both transmissions out (I'm assuming, perhaps incorrectly, that they're close, if not identical to the CB/CG transmissions?), do you think you could measure the OAL and diameter of both shafts, OAL of the assembled gear sets, and if there's any difference of protrusion for either the main shaft or countershaft on the assembled units?

I'm just curious, as I've got access to some 6 speed Honda transmissions that were for E-start only bikes, and I'm curious as to the differences/similarities. I think that the 6-speed with kick start, à la XR200, is different, as they used wider cases, and post '86 had a 5mm longer countershaft (or else the sprockets were spaced 5mm outward) but as far as I can tell, the cases for the 6-speed E-start models are the same as 5-speed kick only or kick/E-start. I can provide the same info on my end once I have the cases split.

[grumpyunk]

Previously on Self-Destruction, a six-speed gearset was obtained from a undisclosed location in the Far East. Question is: Was a six-speed shift drum also obtained?
Looking at the gear pairs, side by side, it seems the position of the pairs is somewhat different, necessitating a substantially different drum arrangement.
As I understand the previous, the kick start end of the counter shaft uses that space and results in a 20mm shaft, the 5, a 30mm. You found a gear(Honda?) with the proper ID and OD that just might make your shaft work in the case you have. Does that summarize properly?
OT {The pictures are so large, reading the text is difficult as a L-R scroll is needed. How in heck did you intersperse words with images. All I can do is 'attach image' and it puts them all at the end of the post.}

tom

[deadwood83]

Originally Posted by franque

Great stuff, I'm excited to see how this build is coming together!

While you've got both transmissions out (I'm assuming, perhaps incorrectly, that they're close, if not identical to the CB/CG transmissions?), do you think you could measure the OAL and diameter of both shafts, OAL of the assembled gear sets, and if there's any difference of protrusion for either the main shaft or countershaft on the assembled units?

I'm just curious, as I've got access to some 6 speed Honda transmissions that were for E-start only bikes, and I'm curious as to the differences/similarities. I think that the 6-speed with kick start, à la XR200, is different, as they used wider cases, and post '86 had a 5mm longer countershaft (or else the sprockets were spaced 5mm outward) but as far as I can tell, the cases for the 6-speed E-start models are the same as 5-speed kick only or kick/E-start. I can provide the same info on my end once I have the cases split.

Sure thing. From my understanding of all the reading I did, there were briefly 6-speed kickers which tended to object to the supermoto lifestyle because each individual gear was made thinner to compensate.

Subsequently, we saw the return of the 5 speed units with kick. button bikes later came back with that 6-speed lifestyle after Honda began to produce them without the kicker mechanism (internal to the cases) which returned a couple mm to each gear and dog. This is anecdotally supported in several places without direct measurements such as https://thumpertalk.com/forums/topic...xr200-6-speed/


This is further supported by the presence of all the kickstart pockets/holes/molding features in the 6-speed 230 cases. The only telling feature is the right side cover having a blanked kickstart boss.



Shaft diameters are identical, with the kicker gear living on a busing/boss that slides over the end of the mainshaft. This bushing/gear piece acts as a bush to increase the effective diameter at bearing seat to 30mm from the 20mm of the shaft. Translations of the part's function description from Chinese are hilarious.

The sole purpose of this bushing/gear/boss interface into the outer clutch basket was to transfer motion from the internal kickstart mechanism into the outer clutch basket which then translated the same motion back through to the crank.

Both the CBS300 5-speed and the CBS300 6-speed use an inner clutch basket spline pattern similar to the output shaft (countershaft) with the retainer being a circlip as opposed to Honda's nut and bolt design. This is probably to cut costs, but should be fine for a sub-40hp street bike.



With Zong's MX-specific motors (NC250, NC450) they switched to Honda's mainshaft fastening method of nut and bolt. The NC series also follows the vein of the CRF250R/CRF450R/KXF250/RMZ250 of having the primary-type kick start outside the cases.



Also, I haven't see anybody else say it... but the DOHC configuration of the NC250 looks identical to an a KXF250/RMZ250, as does the water pump, boreXstroke (identical), cylinder, stud spacing, etc. (for the DOHC). Seems like a fairly inexpensive risk for potentially Japanese performance.

Originally Posted by grumpyunk

Previously on Self-Destruction, a six-speed gearset was obtained from a undisclosed location in the Far East. Question is: Was a six-speed shift drum also obtained?
Looking at the gear pairs, side by side, it seems the position of the pairs is somewhat different, necessitating a substantially different drum arrangement.
As I understand the previous, the kick start end of the counter shaft uses that space and results in a 20mm shaft, the 5, a 30mm. You found a gear(Honda?) with the proper ID and OD that just might make your shaft work in the case you have. Does that summarize properly?
OT {The pictures are so large, reading the text is difficult as a L-R scroll is needed. How in heck did you intersperse words with images. All I can do is 'attach image' and it puts them all at the end of the post.}

tom

6-speed drum, 6-speed forks, 6-speed pawl (smaller diameter roller) and 6-speed pawl spring (stiffer since shorter range of travel) were all procured at the same time as the 6-speed gearset.



I am also quite confident about the bearing because Tianda's service manual shows a picture of the mainshaft with a very non-standard bearing (looks suspiciously identical to the Honda) even though their parts diagrams only show the 5-speed engine (all production Tianda bikes are 6 speed).



In other news, the CRF100 suspension linkages fit and are in. THe seller described the part as "good working order" but I suspect they didn't actually look at the bearings. THe bearings are kept from excessive play by copious amounts of rust. Win some, lose some. This means the CRF100 lift linkage will work perfectly, and manual manipulation of the swingarm shows a MUCH more linear and constrained motion.



Lifan clearly welded the linkage tabs on from the left side first, as both tabs have a slight inclination that direction. I can nudge them both about half a mm to the right, which will re-center the linkage, and the excess slop can be consumed by a slice of the old Lifan sleeve. Honda's design is nice because the bearing caps and sleeves only serve to locate the moving element whereas Lifan tries to compensate for tolerance stacking and fitment by constraining the moving element with fastening force. The Lifan method is not very healthy for welds in the long term. It also explains why on my brother's Kp Mini (stock rear suspension) the back end feels really dead and lifeless compared to even my previous Hellcat.



Billet lifting link ordered.

[franque]

I'm not sure what you're speaking of when you say Honda's nut and bolt design, but my clutch basket on my NX125, which I'm fairly certain is pretty standard, is retained by a circlip on the mainshaft.

[deadwood83]

Originally Posted by franque

I'm not sure what you're speaking of when you say Honda's nut and bolt design, but my clutch basket on my NX125, which I'm fairly certain is pretty standard, is retained by a circlip on the mainshaft.

Hahah that is my bad. I should have specified nut and bolt as seen on the CRF150+ motors. The mainshaft basket end is threaded.






Last night I tore everything off the lifan frame except the headstock so I could leave it on the lift for fitment assessment after cutting the cradle from the XR.



I also puzzled over the wiring. I cut the OEM head unit plug off and re-terminated for a bunch of 2.8mm sumitomo spades. I cannot figure out how Lifan is getting RPM signal on the 2021 models.


On their own wiring diagram it says Bl/W (blue/white, coil output) should go to the dash... but it doesn't. The only wire which goes to the dash from the CDI is the Br/Bl (brown blue) which connects (per the diagram) to a switched positive (key), and goes where the CDI kill switch (ground = kill) normally goes. There's yet another switched positive on the engine stop right below it which connects to the engine stop switch.





On the EFI front, I found the injector which reviewers say cross-references with the Rojo setup. WIth those specs, injector swaps should be possible. Since Rojo is hesitant to release new maps, or give concrete information about how to pull and alter them, injector swaps should provide a way of tuning.



The CBS300 also uses a different manifold mount angle compared to NC250 which means that I will need to attach my own injector bung if I want to get the spray pattern to evenly aim at both intake runners. Somebody makes a weld-on affair for just that. https://billet-speed.com/products/fu...r-holder-small


THe manifold, however, is pot metal. Welding pot metal is.... ehhhhhhh. I may have to settle for JB weld and a freezer/oven fit. If I used the normal NC250 manifold, it would point the intake tract directly at the central frame member.


TIme to email the mfg of that adapter and

[grumpyunk]

FWIW, the bk/y on a lot of china bikes is the tach/coil signal. I expect that the diagram is incorrect to some degree. The injector and associated brain need a tach signal, to know when to apply ground to the injector winding. It may be there is another sensor that amounts to a crankshaft position sensor... or a camshaft position sensor. The latter would make more sense if you injected only near the intake stroke... the former more likely to be used in a 'waste spark' system, firing the sparky plug at each occurrence of TDC(most do).
I think there is a diagram/schematic not being shown here... I know that if I wanted to add a tach, the bk/y wire was the one giving the proper signal. One other possibility is an inductive pickup on the output (secondary) of the coil, much as the 'wrap around' operated tachs use. I guess you need a pinout of the tach, and then follow the wire back to its other end... hard to do from here.
Thinking a bit about the injector and the adapters from billet-speed, the 45 or 90 end of their product could be cut to any desired angle for clearance and pointing purposes. Could the manifold be installed 'upside down' to more properly align? The manifold and the injector should not give a fig as far as operability. The squirt from the injector should be enough to get to the center of flow, and if gravity would 'drop' it too much, change the install angle to compensate by aiming a bit higher than center-of-flow. Maybe?
The billet-speed adapter could be clamped to the OD of the manifold, with a smaller diameter bored hole for spray to pass through. Fillet or curve the adapter to match the manifold curvature, and clamp the injector adapter using the 'clamp points' where the actual injector is captured in the adapter, just pulling the other way.
If desired, a undercut(terminology not my thing here) such as a protrusion, material NOT cut from the adapter, could be left to match the bung hole in the manifold. That would help locate the adapter along the length and side to side on the manifold(centering...). Clamp using modified screw-type hose clamps, and fillet with JB Weld or using rubber/silicone washers to seal the junction.
If you were really into design/construction/etc, you could use some direct-injection style, and port them directly into the cylinder head. sounds like fun! not...
tom

[deadwood83]

THe Xr100 swingarm needle bearing kit came in. The supplied needle bearings are too small. Turns out Lifan saved money by using grom-style (25mm OD, 44mm long) swingarm bushings in the swingarm tube with a rolled sheet metal tube between the bushings. The swingarm is HEAVY, but aside from a GCraft alu swingarm for the XR100M (Motard, JDM) there doesn't seem to be anything else.



After half a day's research, I decided on NK17/20 bearigs (2 per side) and 1 seal per side on the outer edge. Grease zerk in the middle of the arm and one AS1226 thrust washer per side to handle axial loads from the swingarm. The central tube from the XR100 Pivot Works kit will be reused since it is the exact length of the swingarm tube. It's also machined, all oily, and very shiny. It;s probably the bulk of the swingarm rebuild kit cost.



I am still struggling to get the original bushings out. I do not dare put the swingarm in the press because the tube edge is too thin. I think I may just need to get a long flat head screwdriver and hammer on it until the handle breaks, then hammer on the steel end. The press can be used rather easily for the reinstall since the NK17/20 is a machined bearing as opposed to a drawn cup. It can take a weeeee bit of abuse.


In other news, the lifting linkage is awesome. It is built with a brand new Honda bushing setup. If I were a smarter man, I would have bought Pivot Works since they offer needle bearings there as well. When it eventually fails, I can just swap at that time.



HUUUUUGE plus to the linkage upgrade:
I was able to take the 10mm bearing sleeve from the bottom of the old (Honda) linkage and it fit perfectly in the bronze pivot bushing. My cheap ebay shock with 10mm hole is now useful.



Rad mounts came back from the cutter/bender. They are beautifully made. The design is really simple and hard to screw up, but I managed to do just that. Each side is about 7.75mm offset from the frame. No worries though. Considering there will be a steel bolt through the steel rivnut in the steel frame, I think in this instance it is okay to use nylon spacers around the screws to get the offset correct.




I cut up the front mount and made it top hole only. It came out fine. Deburred everything and smoothed the edges with hand filing.


Now... the bad news:
The donor XR200 cradle is about 3" short. I did not properly analyze downtube angle differences.



This means..... it is time to learn welding. I am working on TIG because it can be done for short bursts indoors. It also made the most sense to me, since I have been surface/PCB/SMT soldering for years. Heat area to be joined, dab the filler (solder) on the hot area and not the arc (iron) and move forward. I'm sure I will screw it up a lot but that's fine. If necessary, that can be the last thing I do.


I have ordered all the supplies, just waiting on an argon retailer to get back to me. If I don't hear anything by Friday, I'm driving to Argas to speak with Jake Mecham.

[grumpyunk]

If you have access to a weird chisel, cutting the old bushings, splitting them, will allow them to collapse and be driven out more easily.
I think for welding, TIG is maybe more artful to learn than the flux-cored style. The sheet metal and in general, thin metal was welded by doing a lot of 'spots' and moving on a bit, leaving space between spots, and allowing it to cool. Then come back and weld next to the previous spot. Rinse repeat. A whole lot of connected 'dots' of weld that are then finish ground. Avoids distortion. I don't think you can TIG that way as you have to build a puddle to add material to. I very possibly could be wrong. If you don't like the flux-core, then get the next one up the line, with the inert gas that prevents oxidation.
Just re-read. I thought doing sheet metal, it would warp and hole before you could add material. Guess you will find out. My welding skills are little to non-existent, having only repaired a few things that split. I used flux as it was low investment compared to a TIG/MIG or other. The 'stack of dimes' that seems to be a goal of pro and amateurs made me think that TIG would require more 'hovering' over a spot leading to distortion of thin metal.
There are special chisels that are used to split bushings, such as in transmission repair/rebuild. Once spit, they drive out almost effortlessly.
tom

[deadwood83]

Rear suspension is in. Machined needle rollers on machined through-length bushing, with thrust washers and dust caps.

New linkage is in. Rebuilt using Honda OEM. Sort of wish I went Pivot Works on the linkage.



Radiator swap... again. This time SV650. Easier plumbing. I'll couple with 4" SPAL fan and thermo-bob for true bypass thermostat integration. Also supports inlet and outlet design to support thermo-siphon while bike cools (doubtful much will happen, but for peace of mind)



I can now do this because... I have been learning to TIG. I'm only about 2 hours in, but after 1 hour of playing around, I made a bead I was pretty happy with considering my lack of experience. Made it on the metal frame the KP Mini shipped in. I still have a ways to go, but I am pretty happy with my progress for never welding before.



Transmission: It is in. Had some trouble along the way with a bolt snapping, but it fits with the Honda bearing and one shim washer from the old mainshaft. All new gaskets along the way. I also needed to cut down the kick starter gear to act as a bushing (it has a bearing insert) for the base of the clutch basket. The shift shaft also didn't fit the 6-speed shift star. CRF230 shift shaft en route to replace that. Kick starter removed. I'll measure and order a plug for the right case cover.



Got the cylinder decked by 7 thou. Machine shop locally was very competitive, had out in and out same day, and for a whopping $43 after tax.



To round out almost the remainder of the engine work, I finished a 3-angle valve job with 60, 45, and 31 degree cuts. Photographing the angles with my phone is crazy hard. You can see my lazy-boy dychem job (sharpie).





To Do:

• Investigate the possibility of swapping for the NC250 cam.
• Finish engine assembly. Swap valves, motoseal on base gasket where case seam is, set valves slightly loose
• Weld radiator bracketry
• Extend cradle and weld to frame
• Plumbing
• Fan and temp-controlled relay
• Fueling (still no word from Gary, and the Chinese wanted to sell me the ECU without any wiring or supporting bits for the same price as the whole kit). Wiring harness will be addressed once I do fueling (last) with this.
• Exhaust. NK250 is... close. THe header flange is too wide and im looking for the name of the cup they weld to the piping at the head so I can order one of the proper size.

This is all going a lot faster now that I have a welder, I don;t have to spend so long researching ways to properly bolt/press-fit/seal things together.

[franque]

Looks great! Are you going to have a dyno chart when all is said and done? I was thinking about the problem of an aluminum swingarm, have you thought about the 80/85 2t MX bikes, or would they be way too large?

P.S. the welding looks great, I'm glad you took the plunge.

[deadwood83]

Originally Posted by franque

Looks great! Are you going to have a dyno chart when all is said and done? I was thinking about the problem of an aluminum swingarm, have you thought about the 80/85 2t MX bikes, or would they be way too large?

P.S. the welding looks great, I'm glad you took the plunge.

Dyno? Probably not. I'm at 4500ft altitude so I don't want the numbers from a naturally aspirated engine to make me sad, even if they are better than similar 300cc setups. Plus I have driven many cars with amazing looking dyno charts that just feel... boring.



Alu swingarm I just don;t think there would be any inexpensive way to do it. THe drop-in option is GCraft XR100 Motard (JP-only) with disc brake custom option and that might be about the only option. AN APE100 Type-D (also JP Only, D meaning Disk) swingarm would drop-in, but is built for a 17" wheel. The smaller motard swingarms are either not suited for the power or are built for larger wheels or drum brakes. I'm not sweating it too much because the weight savings from me dieting would be far, far greater hahahaha.


I also had an idea for the upper rad mount. WIth the welder, I could just weld two triangular sensor mounts to either side of the downtube gusset, pass a custom cut rod through, and fasten the radiator right into the rod through the grommets. If I felt really fancy, I could even put a cover plate over the top where the rod passes through the mounts.


It would be very simple, and not require a bunch of precise bending.




Thank you, welding.