80 Bobber

[ShootersHoliday]

this may make the purist (and the decent people) vomit, but here you are:

So here’s the start to my “build”… A 1980 XS1100 (not sure if its a Special, Midnight, G, whatever.. I’m not sure what to name her. I’m thinking Frank…

Stock Yamaha photo & a psudo plan photoshop




How she entered my life… She was an original owner bike. Any of the factory parts such as seat, lights, etc. are available for the cheap. I have pics for anyone here. You all have been very helpful!




About 30 minutes of ownership and all turn signals were off. Putting together some LED’ turn/marker lights.

Old school Sparto tail light (LED). The fender will be replaced pretty soon. I needed the stock fender to mount the temp plate as the PO had a bad title and I am waiting on that getting fixed.

I immediately dropped her about 4”. Need to bring the front down about an inch or so more.



Note the custom kick stand.. 


Hard-tailed the rear, threw on a springer seat (actually pretty darned comfortable). Still a bit to clean up and paint. But looking better for sure.

One of my co-workers Challengers. Pretty freaking sweet!

[BA80]

Y'all keep it up and there won't be any of these old girls left in running order.

In my opinion you took a beautiful bike and uglied it up. But, that's just my opinion.

It's YOUR bike.

[motoman]

Nothin' personnell..........but +1 what B80 stated...........

[natemoen]

Sorry, I agree with the first two. I think the stuff you have done so far make it look pretty bad and poorly proportioned. Some guys have been able to do things like this to these bikes but it takes a long time, a lot of fab work, and usually a lot of money. Many have tried to do it and most all have failed.....and usually failed miserably and then gave up and parted the bikes out. Sad end.

[crazy steve]

Well, it's not like he's trashing a nice original....

It very definately started as a frankenbike, with the '80 standard frame, '78 tank, '79 seat, and XJ forks/standard trees, etc... By the way, that fork/tree combo isn't safe, as it reduces your trail and makes the handling twitchy. Works fine if you're running a sidehack, but otherwise, not so good...

These bikes don't 'chop' well unless you do a lot of work, but it's your bike...

[cywelchjr]

I was going to mention that it started as a pretty badly done frankenbike. And with those triple trees and those front forks without even a front fender/mud guard on there I'd say the thing isn't even safe to ride, it's gonna head for the first ditch it can find. You need to as LEAST get a stout mini fender on there if not a fork brace to keep those wimpy 37mm forks from flopping around. I know with a hardtail your not going to be doing a bunch of canyon carving, but that combo is so flimsy as to IMHO not be safe as is.

And, lowering the rear 4" means the irreplaceable front universal joint is likely to have a VERY short life, as that puts it well outside the arc it was designed to run in. It might even chew up the FD but that I'm far less sure of, and those aren't so rare as the universal joint.

[crazy steve]

Y'know, after looking at the pics again, I'm not sure what front forks he has... At first glance, they look like '81 MNS/XJ forks, but the rotors are much too small. Anybody with a better guess?

Definitately assembled from mis-matched parts...

[cywelchjr]

Y'know, after looking at the pics again, I'm not sure what front forks he has... At first glance, they look like '81 MNS/XJ forks, but the rotors are much too small. Anybody with a better guess?

Definitately assembled from mis-matched parts...

You're right. Maybe 850 or 750 rotors? The main difference is the diameter of the rotors right? The wheels are for sure the wrong ones, look like XJ but that front tire looks WAY too big, at least to MY eye. But yeah, other than feeling (and the opinions were asked for here) that it's a poor bobber job so far, primarily because things just don't flow right. To me, when you do a bobber project, the point is to have a nice visual flow from front to rear, that's just not working for me here. As I said, the bobber part doesn't bother me on this one, he got a pretty molested bike to start with, but the elements are just not fitting together for me.

[BA80]

I didn't notice that at first Steve but yeah, looks like a 750/850 special front end to me.

Measure the tubes. 650s have a 35mm tube and 1100s have a 37mm tube.

[TopCatGr58]

The forks are 80-81 specials, but the TT's appear to be Standards, possibly left over from the frame and a PO front ender damaging the forks?? They are/were not MNS since they were NOT blacked out in the original photos. The swirly wheel is XJ most likely.

Now I have a strong DISagreement with both Cy and Steve regarding the "twitchyness" of his steering with the forks/TT combo. One of these days, I'll take the basket case Special I have, and the Standard I have, and measure/verify the ~6" of trail for both in OEM config, and then find out how much reduction of Trail occurs with the TT swap..but if I remember it correctly, I thought it was that the Sidecar folks would put Special TT's on their Standard bikes/frames/forks....not the other way around.

The Special TT's have the fork tubes positioned closer front to back with the steering axle/shaft....the Standard positions the fork tubes farther away/apart from the steering shaft...so the end result of the different positions of the wheel axles being on the ends vs. leading ends up with the same Trail affect.

I'm sure someone with much better math/geometry/?Calc? skills could measure the distance between the steering shaft and fork tubes on both TT's, and calculate the real Trail amount without having to do a bunch of actual parts swapping and then line/laser marking/measuring!?

My bike suffered a severe front ender event shortly after I got it back to the States from Japan...ended up putting on 4" overlength upper fork tubes during the Dealership repair process....always like the slight "chopper" look, and mine was a special! Unbeknownst to me and possibly also the dealership, but the neck on the frame got bent PERFECTLY inwards towards the engine, but the EASIER steering was attributed to the longer forks? This didn't seem right to me..from my little experience with putting on longer forks on my BICYCLES...the steering seemed much tougher/harder.

But I like the easier steering, and just got used to it. 10-12 years later at a rally, a bike mechanic rode my bike, and then inspected and found the BENT frame neck section. Suggested I swapped frames to get an OEM frame.

Now, MY trail has been reduced(I've actually measured it) from the OEM 6" down to about 2.5" ! Yes...2 and 1/2", so I will admit that this is an EXTREME reduction in trail and does make the bike a "little" twitchy only in that it likes to OVERSTEER a little in the twisties, but I can run the twisties fairly well, just ask MartyA, Mr66, Bruce Gerkin, etc.!

Also, at the last Spring XS rally this year Rman got to ride my bike, and he had no troubles handling it, commented on the EASE of steering, but not that it felt like it wanted to steer into a tree if you weren't white nuckleing it!!!

SO...with the slight change in position that the Standard to Special TT swap would provide, I can't see it making it anywhere near the description of "Twitchy" that you guys are throwing around. I've ridden some OEM bikes at the rallies, and was surprised at the HEAVYNESS of the steering!

I would like to INVITE you to do the Special/Standard TT swap and ride it yourself to feel the real difference it provides. I'll bet that Fredintoon has ridden his TT swapped bike unhacked, and didn't have any tendency to inadvertently steer off the road!

Okay, I'll stop ranting...just had to provide my...I hate to use the term....
real world experience in a drasticly reduced trail, and can't expect the TT swap to provide anywhere near how my bike handles, and it still does handle quite well.

T.C.

[TopCatGr58]

Okay, the forks do Not look exactly like an xs11's, they do have the leading axle special style, but the calipers are NOT the single bolt swivel ones that the True Specials have, they have 2 mounting bolts and a different kind of bracket at the back side of the fork tubes. Again, they weren't blacked out, so I still don't think they were MNS, but probably just regular XJ's, otherwise, they shouldn't/wouldn't fit into the TT's if they were 2 mm's smaller diameter than the XS/Xj's? The wheel diameter size looks right though, the 19 is not much larger than the 17 of the standard...see the OEM photo.
T.C.

[crazy steve]

Okay, I'll stop ranting...just had to provide my...I hate to use the term....
real world experience in a drasticly reduced trail, and can't expect the TT swap to provide anywhere near how my bike handles, and it still does handle quite well....

Jeez, we got TC fired up...

TC, reduced trail is bad for several reasons, but it doesn't automatically mean you're going to crash and die. I've ridden bikes with too-low trail and some seemed fine, and a few were scary... The big problem IMHO is with low trail is the bike is more easily 'upset' and under the 'wrong' circumstances can develop a nasty tank-slapper without much warning, particularly for the unaware. Large bumps in corners, transitions across RR tracks, things that may give you pause even when cornering with a 'good' trail number are the usual culprits. The over-length tubes installed on yours helped bring back some trail by effectively increasing your neck rake. But I knew a couple of guys who had 'underwear changing' experiences with low trail, and at least one guy who got hurt. An experienced rider will have a better shot at maintaining control, but somebody with less skill may not be so lucky.

[BA80]

The question here TC is if those are XJ forks, how would the smaller diameter rotors work?

The pads would only be catching on roughly 1/2 of the face. Those calipers look comfortable on those small rotors.

Possibly the whole front end, tripple trees and all were swapped.

[cywelchjr]

I would like to INVITE you to do the Special/Standard TT swap and ride it yourself to feel the real difference it provides. I'll bet that Fredintoon has ridden his TT swapped bike unhacked, and didn't have any tendency to inadvertently steer off the road!

Okay, I'll stop ranting...just had to provide my...I hate to use the term....
real world experience in a drasticly reduced trail, and can't expect the TT swap to provide anywhere near how my bike handles, and it still does handle quite well.

T.C.

Notice that I specified without either a fender or fork brace, that the combo of the reduced trail (I've read fredintoon's description of the swap to standard trees with special forks enough to remember which way the hack guys go) AND no bracing of the forks as being dangerous. And the primary problem to me is the lack of any bracing. So, I spoke specifically of the COMBO of the two, and feel, fix either one and you only have a bit of a twitchy bike, rather than potential hazard, but I have PERSONALLY had the forks on mine start with the twisting because of things not being just right, and it gets scary, I could imagine it with less trail AND nothing to brace the two fork tubes together.

[crazy steve]

From doing a little net searching, I'm going to say those are Virago forks... maybe off an 1100 version...