|
Post by Adi Nugroho on Feb 28, 2015 5:05:33 GMT
What is the w-force look like? Is it "rideable" for town cruising. Anyway seems you expert using dremels mate. Cheers
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Apr 23, 2015 19:08:44 GMT
Thanks for the comments and they are always welcome. I certainly hope it's rideable, since it will be used to get around in my town. I really feel like I'm really far from expert with dremels, since this is the first project where I've touched anything with a air grinder. It really helps to have a steady hand and learn as much as possible before doing anything too drastic. A little update on the project too. Long stroke crankshaft put into place with fresh bearings and the clutch side assembled with XL cover and BGM Superstrong clutch. I hope it will be enough for this setup, but I'm afraid I'll have to uprate my springs. Also top end threwn into it's place with flywheel to check the clearances. I had to redo the HP4 ducati ignitions wires, since the old ones insulation was cracked and copper was all green inside. Now it should be fine again for ten years or so. I've also threwn in my old Polini engine back to the frame to prevent rushing the parma engine. I've put in a new GS piston with 2mm packer plate and had the cylinder shaved 2,5mm from the top. To compensate the raise, I've opened up the exhaust port 2mm down to match the piston level. Now my problem is that it pulls rather well on first and second gear, but then gets really lean. I think I've got the problem tracked down to my fuel tap, which does not flow fast enough to keep the float bowl full. To get rid of this problem, I've already ordered a BGM faster flow tap, which I'm definitely going to need with the parma setup.
|
|
|
Post by tzsteve on Apr 23, 2015 19:25:41 GMT
a nice looking scoot
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Apr 25, 2015 18:56:05 GMT
|
|
|
Post by smallframetony on May 31, 2015 22:17:01 GMT
nice one! Got a video of it running?
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Sept 17, 2015 20:28:05 GMT
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on May 19, 2019 20:41:26 GMT
Kind a lot has happened since the last post. Hell, it has been almost four years so it would be sad if it hadn't. Got the engine tucked up in the frame Carb shoehorned in with temporary filter from a KTM. Doubted the flow on the original tap, so replaced it with one from BGM. Really should have done this when I replaced the broken tap in the first stage of restoration. The quality of the tap is great, turns easily and has reasonable size outlet. No stretching up the fuel line over the thick barb on the original tap. Tight fit, but I still have all the goodies despite the monsterlike 36mm Keihin carb. Choke knob works and the fuel tap arm clears the throttle cable nicely. Time to admire the beauty of the scoot Decided to add luggage rack. Just because it's kind of an anti-racing looking accessory. Found a shortbody PWK Airstriker without TPS and electric powerjet originally from KTM SX150 so decided to buy it and throw it in. Plus it was a 38mm instead of 36mm, so i have now officially doubled the diameter of the original carb. Drove the summer around and had some problems. The engine idled just fine and revved up cleanly when babying it, but ran rough and tended to "sneeze" when pushed harder. That was one reason to get the 38mm carb without anything extra on it to rule out carb problems. Switching carbs didn't do the trick so to make sure I tried on a handful of jets to no avail. I felt kind of an idiot when a friend of mine pointed out that I had an NGK spark plug cap with resistor AND my spark plug was also a resistor model... After ditching the cap with resistor the engine really woke up. Accidentally pulled a power wheelie on first gear on a first test drive. Now that the engine started making power, problems shifted towards delivering it to the rear wheel. Good quality synthetic motorcycle engine oil was not a good thing with BGM Pro Superstrong clutch and cork plates. Clutch drag was an issue even though the clutch cable was correctly adjusted and still slipped like hell. I ditched the "good stuff" and filled the engine up with the cheap mineral SAE 30 lawn mower oil. The slipping faded considerably but clutch drag was still there. It bothered me, but was overcame by hopping to neutral every time I stopped in traffic. Later I even swapped out the springs on the BGM Superstrong clutch to stiffer ones with new cork plates. Slipping only happened on very high revs on second gear now, but clutch drag was still an issue. It dawned on me that the guys on another forum were right when they recommended spending on a decent clutch right off the bat when I began the build with Parma cylinder. I thought that the 25hp rated BGM Superstrong should be enough. Actually it was very close being enough, but there seems to be no way around the limitations of a thin, original type clutch package. To hell with it, I thought and ordered a Hartz 4 clutch from Mr.Büttner of Lambretta Teile. Time to put the new clutch in! Optimistic me thought that I should be able to swap the clutch with engine in place... silly me... Of course you can't do that, since the clutch basket of a DRT straight tooth primary has a slightly different backplate. Actually it might have been possible to assemble with the DRT back plate, but the damper springs would be wedged in so the clutch basket would be one piece with primary gear. Onwards to pull the engine and prepare it for splitting the cases. All was looking neat inside the engine. No surprises here. Assembling an engine with Hartz proved to be quite a challenge. Small primary gear has to be in place, since you can't pull it after the clutch basket is in place. Getting the back plate to stay put, dicking with the springs so the ends wont get crushed when tightening the basket screws. It was also time to wash the scooter thoroughly when the engine was not in place. I lapped the clutch hub with valve grinding paste to the DRT Runner shaft and fixed it on it's place with strong nut and locktite threadlock. Then it was the matter of assembling the rest of the clutch. Basically the clutch is so big that you have to assemble it "in place". To do that, the clutch springs have to be compressed. After giving it a thought, I got my clutch puller and a big socket. Threaded the puller on the clutch, took out the puller bolt and inserted it with a socket again. This way I managed to pull the springs almost all the way down and lay the cork plates and friction disks. After the socket bottomed out on the puller, I finished the job with the clutch hub cover screws. And there it is! After getting the clutch side done, I decided to smoothen out the transfer ports from the cases to packer plate and cylinder itself. There was quite large step on transfer ports on the Parmakit. I think it's intentionally there to give a fighting chance to run the cylinder without welding and machining the cases. Much better Assembly time It's almost a shame to hide a nice looking cylinder and head behind the cowls of the engine Engine to it's bay
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on May 19, 2019 20:55:20 GMT
Now the clutch problems appear to be a thing in the past. No slipping, nice touch overall on the handle and it's almost surprisingly light to pull. It really pulls now, since I can get almost 120km/h on the speedo on THIRD gear. Fourth is a bit long despite the runner shaft, but it's nice for driving around with low revs. What is the w-force look like? Is it "rideable" for town cruising. Anyway seems you expert using dremels mate. Cheers The W-Force is definitely rideable everywhere since it has really smooth power delivery with LTH Midrange exhaust. You can lob around 60kmh on fourth gear and still climb up small hills without too much effort on the engine. If you tell it to, it will slowly ramp up to highway speeds from there without dropping down to a smaller gear. It's totally another question why would you do that if you have a soundtrack like my scoot.
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Aug 19, 2021 18:52:31 GMT
Just a bit of maintenance in addition to riding the scoot after the last post. Piston still in great shape, no worries there Replaced the rubber bushings with Crimaz bearing+PU sleeve combination. Much more stiffness for the engine mount but also more vibration to hands. Dropped the main jet size a bit since it was a bit on the safe side before and some pulls on a dyno:
|
|
|
Post by tzsteve on Sept 6, 2021 15:46:56 GMT
i found 10 clutch springs too heavy are you using the strong springs that come with the kit
20 bhp is a good amount of power
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Oct 14, 2021 11:44:01 GMT
I don't know about strong, but it's the ones that were provided with the clutch. With XL2 clutch cover the clutch pull is really light and smooth.
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on May 12, 2022 18:32:53 GMT
Dug up this one too after the winter and went for a spin. Gearing seems way too heavy especially after riding on the low rpm polini engine on the yellow one. The current gearing setup is DRT Sport 27/69 primary combined with DRT Runner shaft 10-14-17-20 and stock size big gears 58/54/50/46. According to the dyno the engine makes it's peak power in range of 9000-11000rpm. Went through some calculations on the gearing and the top speed would have been 151kmh if the engine had enough power. 20.3hp is definitely not enough for that with this frame, since a light rider was able to make "only" a 137kmh pull to the radar on an airstrip I already mentally braced myself for the job of splitting the engine and replacing the big primary gear under the clutch for something else. After doing some research I found that the DRT Sport primary can be used with 24 to 28 tooth small gears making primary ratios from 2.34 to 2.88 possible by swapping the small gear only. With the shortest 24/69 gears the top speed would be 135kmh@11k which sounds pretty darn good. In went the order for the 24 tooth gear cog and now we wait.
|
|
|
Post by tzsteve on May 13, 2022 7:44:56 GMT
Try a 48 tooth loose gear for top, Im using 29/69 primaries with 10,14,18,20. And 48 tooth top gear much better, I can tootle around at 40mph (46kph) in top and still accelerate properly if needed. Top speed on dyno is 68 mph (110 kph) Thats with a sensible 17 bhp
I really like The hartz clutch i used one of the 3 part clutch centres with the needle bearings but found the clutch actuating arm was already at 90degrees to the case before pulling the lever, i wanted the arm to be at 90 degrees when the clutch was fully pulled so made a new bronze clutch button that was 3 mm longer, this also helps to keep the clutch button from wobbling in the clutch cover, if you follow what i mean
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on May 13, 2022 9:11:39 GMT
I definitely know the rattle when clutch is not pulled.
27/69 with 48 loose gear would result in 145kmh on fourth, which is -7kmh from current gearing. Since I intend to do some 1/8 drags with this for fun, I think the shorter primary will work better for me.
|
|
|
Post by tzsteve on May 13, 2022 17:21:40 GMT
Yep i agree with that lower gearing would be better for sprinting. 11000 rpm is a lot of revs. I think that is about the limit even on the track, id be worried about the bigend trying to escape from the rest of the engine
|
|
|
Post by tzsteve on May 14, 2022 10:10:47 GMT
Yep i agree with that lower gearing would be better for sprinting. 11000 rpm is a lot of revs. I think that is about the limit even on the track, id be worried about the bigend trying to escape from the rest of the engine I could be wrong on the maths but your gearing with 24/69 & 46/20 gives a top gear of 6.6 if you used a 48/20 with 24/69 that would give 6.9 not a bad ratio that would give about 77 mph or 123 kph @ 11000 only a drop of a few mph and a bit less of a jump from 3rd to 4th and much more achievable .
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Jun 7, 2022 22:19:05 GMT
In goes the z24 primary gear Couple steps later: You could never quess what has been laying over here: Went on a test ride. Power comes out quite violently and there is no need to rev all out to hit the power band on the next gear. Beautiful evening and almost as pretty scooter.
|
|
|
Post by tzsteve on Jun 9, 2022 10:06:10 GMT
Sounds like nice ride, and all the power useable .
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Jul 3, 2022 15:31:56 GMT
I have been struggling with a power dip between 5000-6500rpm more or less the whole time with this engine. I have changed the tap to a fast flow one, smoothened out the transfers, hunted for air leak, done lots of fiddling with jets and even switched to another PWK carb. Couple days ago I decided to have a proper look if I could get rid of the dip. I tested the engine with SIP Road Banana, which pretty much got rid of the dip but also all the power too. Switched back the LTH Midrange and swapped the plug to a fresh one at the same time. After changing it just refused to rev properly and made weird sneezes. It got better by making the spark plug gap smaller, but after that I was at the starting point with the dip. After this I decided to take a look at the ignition and turned the stator plate clockwise to check if I was running too much advance. No dice, only made it worse. At this moment I realized that I might be onto something this time. Turned the stator plate counter-clockwise to add some advance and boom, mo more funny business down low. Made fresh markings on the flywheel and cases, stroboed it and noticed that my previous timing marks have been off by a mile at least. It turned out that the 20.3hp on the dyno was produced with whopping 7 degrees of advance. Turned the stator plate some more and went for a spin:
Now that I've found the power in this engine, I think I have to swap back the longer primary gear
|
|
Yoshi
100 Sport
Posts: 75
|
Post by Yoshi on Jul 15, 2022 22:00:11 GMT
Longer primary gear is back and scooter got a run on the dyno again. The advance on peak rpm is now conservative 14 degrees and it made 22,98hp.
Question follows though. Can you run 18 degrees of advance (on peak rpm) with the W-Force or is that too much?
|
|