GEBE I'm Ready to do

Discussion in 'Rack Mounted Engines' started by BTB Wild, Sep 15, 2007.

  1. BTB Wild

    BTB Wild Guest

    I like the GEBE Robin/S 35cc kit as one of two I'm considering. Attached is a pic of my bike ( and I have all specs). Does anyone forsee any issues problems with the install. Are the wheel/spoke specs sufficient enough to use the stock wheel? The wheel is a Syncros Big Box w/ stainless steel 14 gauge spokes ( 32 spoke) brass nipples and tire size is 26X1.95" Intend to get trail gearing. I don't want to drill new holes if it can be avoided.
    I'd like to get a kit installed soon! Thanks for the help!

    Attached Files:

  2. Alaskavan

    Alaskavan Guest

    I don't run Gebe, but I do read. I think you will have two concerns. 1) The Gebe mount is not supposed to be used (perhaps can't be used) with a quick release axle. Might be able to frame mount it. Check out Bama's posts. 2) The spokes may not hold up. Check out Bama's posts.
  3. BTB Wild

    BTB Wild Guest

    Thanks, GEBE told me I can swap out the axle no problem. If the spokes are an issue I'll have to consider a wheel upgrade. I'm also considering a chain drive unit from Staton. Is free pedaling a feature shared between the two systems? Is there more drag with a chain unit? Thanks
  4. bamabikeguy

    bamabikeguy Active Member


    Ready to help, but consider the Tanaka33 before committing, the shipment is due to arrive within a week I hear....

    Plus is the tank location and "possibility" of larger fuel tank replacement (1.5liters/50 oz.) Power is probably MORE than the 35, because you can operate wide open for a half hour if need be.

    Minus is mixing gas/oil, but it is EASY to get the hang of that. Im heading to the County Seat, 25 miles away, this morn.

    Stashed behind the weeds, near the big log with the mossy bump, on a backroad rarely traveled, is a 1/2 gallon of gas I stashed there 2 weeks ago.

    My own fillup station.

    Bike looks good, spokes should work, think about punctureproof tube on the back, a $10 investment that may save $50 in aggravation.

    If you go with the R/S, read Sam/Starr/Lars/Petes advise....

    Learn "framemounting", THAT IDEA IS A WINNER AND A HALF !
  5. bamabikeguy

    bamabikeguy Active Member

    Framemounting should make the present wheel okay, you just have to take care on the spoke-ring install, which isn't that big of a deal when you read how it's done.

    GEBE pedaling is barely noticable with the belt tensioner engaged.

    Reserving my Staton opinion at present...
  6. BTB Wild

    BTB Wild Guest

    Yeah, GEBE told me those Tanakas were due to arrive.....I considered the fuel and fuel tank issues and it seems like a trade-off either way. Mixing is no problem and I could carry a spare gas bottle if necessary so I'll definately look into the 2 stroke.
    My other thought is this.....bicycles are relatively cheap ( well...not my GT anyway) I thought about purchasing a budget bike that would accept these kits with minimal modification and hassle. So I'd be happy to look into full suspension models ( and maybe hard tails with a nicer seat) that would install in a breeze. I don't want to Frankenstein the GT to the point where I'm spending money to undo the original bike just to accomodate the engine. I'd say $200-250 range is not unreasonable. Thanks again. You guys are great here.
  7. Jim H

    Jim H Guest

    Gebe has a photo gallery/testimonials section with many bikes of that type (full suspension) and the folks who have them seem satisfied. I have the 40 tanaka and love it but if I buy another one , it will be the 33 tanaka... better gas mileage with much the same performance and mph.
  8. bamabikeguy

    bamabikeguy Active Member

    I think you are being VERY wise in this decision.

    Random ideas (sorry to knock out a lot of things in one post, but best to fill the plate when serving food for thought)

    One thing about suspension on the rear. You can just about duplicate the "feel" with a $20 shock absorber seat post. It has an Allen's screw on the bottom, you can adjust from "soft" to "firm". Rear suspension puts extra stress on the "mount strap", the thick band GEBE sends to keep the motor mount attached to the bike.

    The stress using rear suspension CAN be overcome, of course. Loktight on the connection bolt, zip ties for extra security. But phat cruisers with no suspension will do nearly everything a mountain bike will...

    And on front suspensions, unless you do some adaptations or reinforcements to the legs of a basket/rack, those two legs will bend. Quick release fronts also have some "basket issues".

    On a non-suspension bike, baskets or front racks cause no problems.

    Reading, you have a good idea what your future plans/additions would be, picking a 50 pound aluminum cruiser with 7 speeds or 21 speeds, with 1.95-2.125 inch tires, probably gives you the MOST adaptability.

    Once you use a 12" gel saddle, you'll never go back !!

    I emphasize curved handlebars because you can sort of sit back, instead of feeling you are leaning "over" the front wheel.

    Craigslist in you area might have some cruisers at a bargain. If it has FULL FENDERS, you will have to drimel away some metal so the belt can pass thru, or switch the fender out with a half fender. (Or discard the rear fender altogether).

    If you have time to look in bikeshops, Sun brands are pretty much Generic Schwinns and Diamondbacks.

    However, with the 12gauge steel wheel on the rear, then mirror/ are bumping $275.

    Sun Retro Alum 7's were the ones I found with half fenders which were easy to work with, no drimel needed. You can get a cruiser without fenders, then add them later.

    If that bike shop has a Sun Comfort Rover, I just took the Greygeezer 50 miles roundtrip today, pretty comfortable.
    Last edited: Sep 15, 2007
  9. BTB Wild

    BTB Wild Guest

    Bama, tons of great info to digest... and I appreciate all the feedback you guys offer to us newbies. Although the engine to drive wheel distance remains a constant ( with GEBE mount) I realized right away that the engine would push/pull against the strap ( on my full suspension) ....eventually loosening or breaking. An issue that can be resolved with a modified strap, maybe involving a spring etc. I'm pretty certain I want to maintain front suspension however. I will check out those bikes you mentioned.
    I was in Walmart today and saw dozens of cheap bikes. They all " look" great and the prices were laughable. $69-$139 price range. I think I'll need to do alittle better quality wise.:lol:
    So far I'm stearing toward the 35cc Tanaka GEBE kit. My GT rides soooo nice
    that I'm tempted not to mess with it. But I have no will power so we'll see what my research bears out. I'll report back and thanks.
  10. Alaskavan

    Alaskavan Guest

    As far as the front suspension, I think Bama's real concern was if you're going to attach a basket or rack to the front. I have front suspension, and would advise that you want a good unit, and should keep a close eye on it. You don't want the front end getting squirrely on you at 30+.
    As far as the rear suspension, you'd want the motor attached as firmly as possible. If you ride at all conservatively, you probably won't have any problem. I don't have rear suspension, but unless you're as crazy as I am, I doubt you'd give the mounts as much abuse as I give mine. I would recomend adding extra struts. Have you checked for clearance for the drive ring? It might be pretty hard to alter that frame if it doesn't have clearance.
    Last edited by a moderator: Sep 16, 2007
  11. BTB Wild

    BTB Wild Guest

    Yes AL I've got clearance. The only squirrely issue would be me going 30MPH...not gonna happen.:oops: I'm interested in trail gearing, hill assist, back road bee-bopping, tame wooded trails etc. I don't think the suspension will be an issue for me since I'm not looking for speed. No baskets on the front end either.
    While I'm thinking about it let me ask this......does the engine mount have to bolt to the axle? Could you use a knock-out or pre-drilled hole on the frame if parallel to the axle ? ( on the tail fins) How would this 1/2" displacement affect the system?
  12. Alaskavan

    Alaskavan Guest

    Hi BTB,
    Bama has a real good thread showing detail of frame mounting for a Gebe. He seems to like it. I trust his judgement and skills. I think the salient point is the distance between the mount and the axle. Not the method of acheiving it. I don't know, but I would think that going to frame mount would mean you could retain the quick release axle.
  13. BTB Wild

    BTB Wild Guest

    Yep, that was my thought.......nor have to drop the motor & mount to fix a flat tire. But now we're getting into geometry. Maybe more of a hassle. Or I could carry 2 spare short bolts and wing nuts to temporarily move the engine mount to the knock-outs while changing the tire/wheel etc. A reoccuring theme for me is... the issue I never thought about will be the issue that bites me in the *ss.:oops: Less analysis and more "git -er -done" might be in order here. Fix it when she breaks......but just get the dang motor on the bike.
  14. Alaskavan

    Alaskavan Guest

    I think you're asking the right questions. And I think you've asked most of them. If I was you, I'd check out Bama's frame mount thread, make a decision, and jump. After collecting info, every day you delay is a ride you didn't take.

    For me, my friction drive don't work in this rain. Gonna go check the crab traps, unless the wind keeps me off the water. Oh well.
  15. BTB Wild

    BTB Wild Guest


    Bama, there are a few GreyGeezer dealers listed in my area.:p I read your thread about bike types and the issues you mentioned about body posture, center of gravity etc. are concerns as well. My GT is a great bike but not the best to motorize IMO. I've laid the bike down on trails because the frame is too high and I can't simply jump off the front of the saddle and use my legs to break the fall. No doubt with engine I'll ride faster and fall harder.Looks like that SUN addresses most ergonomic issues and that's sweet. I'm going to take a look at one this week. Thanks.
  16. bamabikeguy

    bamabikeguy Active Member

    The more I ride the Greygeezer, (Sun Comfort Rover) the more I like it.

    I'm keeping the rear derailleur on 7, the smallest sprocket ring, and only using the front on the left hand handle.

    Basically getting used to switching between 2 (14th gear) and 3 (21st), pretty much the only 2 speeds necessary for starting out and staying at top speed.

    On 7 speed bikes, I stay in 7th 99% of the time. But I found yesterday, on a 3 mile stretch to get the newspaper, in 14th gear, half throttle, kind of just puttering along, peddling for exercise. This also increases "miles per gallon".

    If you had the trail drive gear on, and were using those lowest 7 gears, I imagine you could climb some pretty steep hills. I ride around pasture trails, but nothing too steep, because the downside is the tires being street tires, won't be getting the grip of knobbies.

    Tires just aren't as "switchable" (street to knobbies) as changing the drive gears from trail to highway.

    However, "if you frame mounted", bought a second spoke ring, had a second rear wheel and with quickreleases on front, I imagine you could rotate from "street" setup tires for everyday use, then put the other 2 "knobby" setup when you wanted to do a weekend of outbacking....

    That would be "future" thought, but framemounting from the get go would give you that expandability...playing around with the rear tire is SO MUCH EASIER having it framemounted.

    Carrying as much camping gear as the setup I have on the red Rocinante would take some creative thinking, but if I did want to take Greygeezer out on the road for a week, framemounting would also allow switching my saddlebags from "behind the handlebars" to "attached to the mount, on either side of the rear wheel".
    Last edited: Sep 17, 2007
  17. larymor

    larymor Guest


    Hello BTB.....I have the R/S35 mounted on a $100 Aluminum Vertical MB with full suspension. I had to frame mount the engine because there was a bolt in the way by the axle ( its easy to frame mount ) ...once you frame mount you can remove the wheel without disturbing the engine....way better! I had the rear strap break on me once at about 75 miles( the bolt broke)..fortunately I had a zip tie on and it held so no problems with acceleration....throttle cable stretch's when strap breaks. I replaced the bolt and used loktite.....added another zip tie so there are two....extra insurance. I know a lot of the guys prefer the tanaka because of the fuel tank thing but I like the Robin cause I can pull up to the gas station and fill it up without the oil mixing hassle and the sound is not as irritating as a two stroke. I just carry a MSR fuel bottle with me and I have never been stranded yet. 230 miles and smiling :grin:
  18. BTB Wild

    BTB Wild Guest

    Any hills out your way Larymor? I'm in W PA so I want to make sure I get the right engine. Thanks for your input.......I've been on the fence about the bike too...but I'm going to frame mount the dang thing onto my GT and be done. I could always switch bikes if i'm not happy. Can that Robin pull a modest hill ?( 200 lb rider)
  19. larymor

    larymor Guest

    Power to propel you...

    only hills are underpass and overpass..pretty flat mostly, but I weigh 245lbs and it takes me right over the freeway overpass etc. without a problem...up and down the trails by the river etc. I don't think your 200lbs would be a problem at all...just my opinion. If you frame mount on your GT that resolves the axle release and length issues in one fell swoop. My R/S35 gets 28mph with my 245lbs on it!

    Attached Files:

  20. Hive

    Hive Guest


    Check the pawn shops, if any, in your area. You might be very pleasantly surprised.

    And go all the way through the GEBE Dooz and Don't Dooz and related topics and the sticky on GEBE.

    My experience gives the Tanaka the edge. Big clutch, lots of torque, simple, if you can find one.