Re: Water cooled Hobbit kit, 4 cheeeep!

http://www.treatland.tv/TJT-variator-derbi-variant-honda-hobbit-p/derbi-moped-tjt-variator-honda.htm

This should waken it up. I still use the stock rear spring. The heaviest weights are only 3 grams. Also, a real pipe would help. A motomatic destroyer really awakens these hobbits as well. I also use some cheap taiwan "2k" springs.

If you go to https://www.1977mopeds.com/blog/2009/05/02/polini-cup-may-event/ and click the on demand button, then helmet cam, then twist and go with tommy, you can hear my bike and see what I am talking about. It's a bit gnarlier than most hobbits, but shows you what a hobbit is capable of.

Re: Water cooled Hobbit kit, 4 cheeeep!

Downhill Harvey (OFMC) /

Where's the "on demand" clicker?

Re: Water cooled Hobbit kit, 4 cheeeep!

Wow, that thing rips :|

That TJT is all you did to the drivetrain? Nice, I'll recommend that then.

He's not going to switch pipes. I already suggested a Motomatic b4 he ordered the Proma, but he didn't want to spend too much money on it. He already bought a new racing crank, Malossi 70cc kit, 21mm Dell'orto, 6 roller variator and new rear pulley, so that set him back a pretty penny.

I dunno if he wants to spend $150 or so on another variator tho, but we'll see. Thx :)

Re: Water cooled Hobbit kit, 4 cheeeep!

Thanks. TJT and clutch springs is all I did.

Harvey, heres where to find the on demand button.

Re: Water cooled Hobbit kit, 4 cheeeep!

Incase anyone is still looking for a water pump solution. TS racing has these for water cooled Karts

http://www.tsracing.com/store/showdetl.cfm?&User_ID=2011297&St=5635&St2=82756313&St3=80263717&DS_ID=2&Product_ID=4369&DID=7

Basically has 2 "belts" (HD O rings) that you can attach to say the crankshaft or sprocket (you would have to make your own pulley) But since its a mechanical pump less to worry about if something electrical went wrong.

Re: Water cooled Hobbit kit, 4 cheeeep!

Downhill Harvey (OFMC) /

Thanks Tommy.

Re: Water cooled Hobbit kit, 4 cheeeep!

Pablo Puchasso /

SchijnHeilig does have a point about the rear pulley it would seem. I mean that seems to be the scooter/hobbit guys big secret. He adapted some scooter pulley for the back right?

Also, I think Naz has a really good point that hasn't been discussed on here. We need to discuss some standard for 'blasting.' Maybe a unit of measurement. I say we call it the blaston. (ie) My bike is doing 800 blastons. It could also be like a scale or curve. I'm joking of course, but there is some validity to it.

Re: Water cooled Hobbit kit, 4 cheeeep!

racing seems to be one form of proof.

His transmission helped for sure, but his kit was also rated 24 hp to mine that was probably rated at 8 hp. You do have to have a good transmission to take full advantage of that power of course.

Re: Water cooled Hobbit kit, 4 cheeeep!

ᴛᴇʀʀʏ ᴅᴇᴀɴ /

tommy, where did you get the 24hp number? do you know what kit it is for sure? all the smart motor guys who were standing around him when we were talking about it after most everyone left said it was probably rated for more like 18hp or so, which is still a lot.

also, isn't that athena more like 11 hp or something?

Re: Water cooled Hobbit kit, 4 cheeeep!

Ramero is the one who told us it was rated at 24hp. We all agreed that on that bottom end, its probably more like 15-18.

There is no way in hell that my bike is 11 hp. The motomatic bike was brought to the dyno and tested at 10.5. The kit and porting on that thing are way gnarlier than mine. I would guess mine after porting is about 9.5 based on the motomatic testing.

Re: Water cooled Hobbit kit, 4 cheeeep!

) Cupermcnewbster ( /

and yet jeff still had the fastest lap time.

So he had nearly double your power. Insane!

Re: Water cooled Hobbit kit, 4 cheeeep!

Back from the dead.

Travise, or anyone else attempting to use this kit?

My results are lots of frustration. It runs but the compression is aweful town. Turns out the stroke is not right on at all. Piston backs off about a cm before the actual edge of the cylinder because the hobbit stoke length is shorter. I'm brainstorming a way to actually shorten the cylinder- because everything else seems alright. The exhaust port opens all the way and it's jolly town. It'd even idle fine, but no power. Can't fuck with the head, just need to shorten the cylinder a bit to get some compression.

Hopefully I didn't just end up with some weird long stroke version of the thing.

Re: Water cooled Hobbit kit, 4 cheeeep!

The stroke is probably the same, but it's not the stroke that decides where the piston sits in the cylinder.

It's a combination of crank placement, case height, piston length and conrod length that decides how high the piston sits in the cylinder.

If you're having trouble getting the deck right, you can try finding a piston with the pin lower in the piston, so the piston comes out higher. You can also try to find a longer conrod, shave the cases or shave the cylinder (top or bottom). Altho shaving the cylinder from the top will alter the timings.

Re: Water cooled Hobbit kit, 4 cheeeep!

Yeah, the stroke is a little bit short on these. Deck the case a little, there's room there. Did you JB weld up that top corner? Thermo-shyphon or radiator?

You've got ONE WEEK to get this running, hurry up.

Re: Water cooled Hobbit kit, 4 cheeeep!

I fucking KNOW! ONE WEEK! And only 3 actual days if you don't count my work days.

Thermosyphon seems to cut it. Granted I haven't taken it on more then a few short rides because it lacks POWER! Even pushing it as much as I could it never scared me with it's heat output.

I did the whole sham-a-lam on it, Travise. New bearings and seals and crank and blah blah lot's of case work, jbwelded up the ports. Grargh!

I think I'm gonna deck case as much as I can, since it is nice easy soft aluminum and then probably some from the cylinder... I need to make up almost 10mm here!

Jeez.

Re: Water cooled Hobbit kit, 4 cheeeep!

im bringing my (now basic compared to you nerds) hobbit build to Portland, i leave on sunday and arrive on thursday. motomatic, athena, 24/4pedal.

I havent broken the crank yet, i have about 600 miles on it,(green crank) we'll see how it holds up against you scooter kit duders. i have a good feeling about it. feels really solid. full rebuild this time and stock rear spring, plus the variator of dreams.

during FTW i left the pack in a hurry and around the 60 mph mark i felt something like the belt slip or the clutch let go momentarily. for those milliseconds i was sure my crank broke again. eerie feeling.

Re: Water cooled Hobbit kit, 4 cheeeep!

I've got a LOT to do before this freaking scooter kit will work for me. I mean, I now need to split the case, and shave the case by about 10mm- THEN put it back together- Rewire it, Plumb it, and Tune the fucking huge Carb. Oh, and I still need to strip and powdercoat the wheels. Oh, and the whole while I'll have to just keep my fingers crossed that I won't hit some other stupid hangup. I guess I could get that all done in a day. Phhh...

You'll most likely see me riding my mediocre Orange hobbit all weekend.

Next build is all moped parts- and air cooled.

Re: Water cooled Hobbit kit, 4 cheeeep!

im pretty sure you dudes will be surprised at the hustle from my air cooled athena.

Re: Water cooled Hobbit kit, 4 cheeeep!

_The exhaust port opens all the way and it’s jolly town._

so wouldn't decking your cases only serve to raise your piston above the bottom of the exhaust port at BDC?

I think you need to take it off the top of the jug,

Re: Water cooled Hobbit kit, 4 cheeeep!

Nope, I just mocked it up. The piston travels back about 8-10mm before the exhaust port. In other words the whole jug needs to move back at least 8mm.

Re: Water cooled Hobbit kit, 4 cheeeep!

Downhill Harvey (OFMC) /

I kind of like the longer connecting rod idea. But where to find one, I just calipered the case thickness, where the cylinder meets, and it's a total of 8mm. You might be able to shave a max of 2mm. You have plenty of cylinder skirt room, but the case isn't thick enough. Eigher way, it's not something a dremell could do. You're still going to need a professional machine shop, and if you are going to a machine shop, I'd take it off the bottom of the cylinder. Leave the case full strength. I think a simpler route would be the longer piston (fron wrist pin to top of piston) idea. Finding that piston will be real hard, especially with the correct or correctable piston skirt.

Re: Water cooled Hobbit kit, 4 cheeeep!

Well... I just got out the ol measuring tape and it looks like I need a realistic 5mm, so If I can deck the case 2 mm then I'm almost halfway there. Also, I really think I can probably go farther then that.

Fuck it... Tomorrow... Full steam ahead!

Re: Water cooled Hobbit kit, 4 cheeeep!

Downhill Harvey (OFMC) /

Check out the case bolt holes, they're too close to the top.

Re: Water cooled Hobbit kit, 4 cheeeep!

Josh Besecker /

I want to know how this worked for all involved parties? Bout to go wandering down this dark path... lc scooter kits on hobbits~~~ Pita, or Atsb (ass to seat back) ???

Re: Water cooled Hobbit kit, 4 cheeeep!

you have to shave quite a bit off the top of a minarelli horizontal cylinder for the piston to head distance to be right and the stud holes in the cylinder need to be opened up. there's another scooter kit that's easier to do, can't remember it off the top of my head though.

Re: Water cooled Hobbit kit, 4 cheeeep!

Peugeot speedfight. Or the malossi h2o kit that treats just got back in stock.

The peugeot scooter kit transfers are giant though. Requires case welding around the transfers and behind the stator/variator.

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