donor, pre-operation

[hamishbarker]

My first post, here goes! The conversion kit is ordered and I found a donor.

It's ugly (the original owner seems to have had an interesting concept with the seatpost mounting!) and probably will be a little heavy (16kg at the moment), but the junk components will be replaced by some vintage xtr (incl. nice old xtr v-brakes!) that I have on another frame, as will the wheelset.

But it was cheap, and the geometry looks good I guess. Not sure if the fork offset is going to give problems with the cluster, will repost when my kit arrives and the work proceeds!

Any other Cruzbikers in the top of the south island, new zealand?

height="437"

 

[ghglenn.ku]

oooooo, barracuda...

Looks like a good one. Spent a week in Mapua a few years ago. Does that count? Also, nice microbus!

 

[Jake]

Brakes

It's hard to see from the photo whether the frame has a disk brake braze on for the rear wheel. If so you can simply swap the brakes round (as you'll need to swap the wheels round). If not you'll need to get another V brake for the front wheel as the conversion kit cannot use disk brake up front. You may even have to file off the front disk brake braze on. If you do decide to test ride with just one brake, I'd advise making it the front one.

Otherwise the frame geometry looks good - plenty of room to dial in the perfect seat position / recline. Enjoy.

Jake

 

[hamishbarker]

post-operation

The kit arrived, and quickly! Many thanks to Maria for that (Or at least that's who the fedex system said dispatched it).

I had a few minor issues with the conversion:

1. seatpost change. the old one was 30.2mm and normal (with integrated clamp) seatposts seem to be not compatible with the supplied clamp, so a trip to the reuse/recycle center found an old straight steel one (and extra set of handlebars for $6 total!). The 27.2mm steel post was then shimmed it up solidly with some thin aluminium. It seems solid enough and will do for the moment until I get a proper alu post to fit the frame and supplied seat clamp.

2. fork. I actually put the old red suspension fork and nice short stem on a different mountain bike I have, which had only a disc brake on the back, as I had a spare disc brake in the parts box for the front, so now that bike has discs front and rear. The fork from that bike (an old green ti-spring manitou, great fork but no disc mounts, hence the desire to swap) had clearance issues with the steel cruz front conversion brackets, so (musical chairs!) took the steel fork off the xtracycle and now all good, no front suspension but lighter than a suspension fork and there's still the big swingarm under my rear.

3. cables. The old cables were manky, so replaced most of them, and all housings. Cables and particularly gear shift cable housings are not as cheap as I expected!

4. bottom bracket. The donor bike BB was dead (right side bearing disintegrated) and very hard to remove (even after I googled to confirm which side is left hand thread!) but not a problem overall, as all the actual components on the conversion are old shimano xtr from a second old mountain bike with old shimano (pre-cartridge bearing era - how old?), and that bottom bracket is fine as well as much lighter.

The final conversion: 17.5kg (not a light bike! but that swingarm is probably valuable just for the weight of scrap aluminium it contains!).
I measured the weight distribution (with rider on board): 57% front, 43% rear. This seems close to Mr Tolhurst's guidelines, and maybe I will set it a few % less on the front (seemed rather front heavy when braking down the driveway) when I get comfortable enough riding it to lay the seat down more. The seat comfort and hand position seem good for now. Knee clearance also seems ok.

I rode slowly down the driveway (probably steeper than all "first ride" recommendations!) ok. Tooled carefully around on the street with some failure (the bike would get this funny lean and "not answer the helm" as boaties might say) and some success. It had just gone dark and just wanted a quick trial, in a couple of minutes I could manage pedalling with what I'll call "approximate" direction control. I'm looking forward to more (and better!) riding.

I also can think of a nice big rack design to perhaps put on the back (As those toptube stickers always say "my other bike is an xtracycle...") which could triangulate from a fixed point made by old quick release fitted through the old bottom bracket shell, and a mount at the seatpost, with triangulating bridging elements from the BB up to the rear of the rack outboard either side of the swingarm - a benefit of this bike's non-URT suspension. Perhaps a big wide flat deck with a bit of a rail around the edge for tie-downs, or just a simple light basket concept, or something. Using QR through the old BB shell, and one around the seatpost could make the whole rack easy to put on or off when needed or not.

Things I'd like to improve:
1. weight. 3kg more than sofrider's advertised weight (and no kickstand yet). Feeling the weight of the steel front drive conversion brackets in my hand, I can see how the softrider's dedicated fork could save weight (as does their clearly lighter rear triangle compared to my "let's use a large chunk of aluminium" swingarm.). Not really anything that can be changed though, as the components are not to blame, it's just my low quality, heavy donor frame.

2. no kickstand, and nowhere easy to mount one. And the bike does not like to lean quietly against walls. If I go the QR-though the old BB shell route as mentioned above, I may use some right angle bracket to make a kickstand mounting point there.

3. Fenders. Call me slow, but I prefer the road grime not to be sprayed onto me. The funky reversed fork and swingarm are going to require some non-orthodox mounting solutions (or just ride the fenderly unchallenged bike when it rains).

Big thanks to John T and the Parkers for the great design and quality of the kit and quick service! Heres to many comfy miles!

 

[Charles.Plager]

Very nice! (And quickly done,

Very nice! (And quickly done, too!)

I wonder if you can use the old bottom bracket whole to do something with a kickstand?

I wouldn't worry too much about the weight (unless you're light and have lots of hills). You can always get a lighter frame to convert later...

As far as riding, if you haven't already, take a look at Kim's videos. (You can also read about my experience and even some hints here).

Cheers,
Charles

 

[hamishbarker]

Question regarding chainstay to front axle bracket joints

I am in New Zealand. There are hills!

Went for a ride this evening while walking the dog around the neighborhood. I really need to fix my squealy brakes, but at least everyone hears me coming down the hills. I did pretty well, rode up most stuff that I would make up on my mountain bike, but a bit wobbly when going intentionally slow up some hills to let the dog (dachshund!) keep up with his little legs. It seems that the learning curve is not as bad as I thought it might be when I first rode the bike.

I noticed something that I'm not certain is quite correct in my conversion assembly:

- the joints between the chainstays and the steel front wheel axle brackets (the fancy conversion brackets) are a bolt, two plastic washers and a steel washer. The inner hole of the chainstay joint is threaded, so no nut on the bolt. I have assembled with one plastic washer on either side of the steel bracket (keeping the steel bracket separated from the aluminium chainstay joint, and one steel washer on the outside keeping the bolt head from impinging on the aluminium. But the plastic washers don't fill the joint - there seems to be perhaps 1mm of clearance. Is this correct? If necessary I can post a picture.

 

[John Tolhurst]

Put all washers inside the

Put all washers inside the yoke, completely fill the space, then you can tighten the bolt without risking bending the yoke over. Don't worry about a washer under the bolt head.

 

[hamishbarker]

thanks!

Thanks for the response John. All good now.

Today I rode to work, 21km each way, with a swing bridge and a few gravel km at the end, swing bridge was interesting!). Thankfully it's almost all on dedicated cycle paths. I was pretty slow in the morning, with front derailleur issues (loose cable-securing screw I think), a couple of stops to adjust the telescopic tube (to reduce knee-hits, see below) and a few wrong turns here and there. But I set up my GPS to give a 23km/h training partner for the ride home and "won" by 1.1km (apart from the last steep street to home. ).

There are a lot of keen bikers at work. I had lots of comments, some complimentary, but they do all think I'm a bit nuts to build and ride such a bike. It was comfy, although I do need to get new handlebars, as I have limited knee clearance, with occasional knee touches to the bottom of the gear shifters. I think some porteur-style bars might work well to curve up away from my knees then back down for more vertical hands (the current bar is a low-rise mtb bar, not flat, but only a few cm of rise.

 

[Charles.Plager]

Keep it up!
On both of my

Keep it up!

On both of my Cruzbikes I use this adjustable stem. It might give you just enough room for your knees (I don't disagree at all that another shape of handlebar might work a lot better for you, too).

 

[Doug Burton]

Kickstand Solution

I solved the kickstand issue on one of my conversion bikes by attaching it to the front fork. Since it keeps the front end from rotating, the arrangement is very stable.