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Started the KTM build

Posted: Sun Apr 07, 2013 8:29 pm
by Lots of steel bikes
A few pics of the KTM coming together. Mostly Dura Ace from different eras. Decided I prefer the look of a 7200 rear derailleur over the 7400. So if anyone has a 7200 they are wishing to part with let me know.

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Re: Started the KTM build

Posted: Sun Apr 07, 2013 10:11 pm
by Saro28
If it's not orange it's a lemon :lol: . I know the moto pedigree, any story to the cycling side of ktm? Yep, don't mind early DA.

Re: Started the KTM build

Posted: Mon Apr 08, 2013 7:31 pm
by Lots of steel bikes
Saro28 wrote:If it's not orange it's a lemon :lol: . I know the moto pedigree, any story to the cycling side of ktm? Yep, don't mind early DA.
Here's some info

Check out the pic of bicycle frame testing.

Re: Started the KTM build

Posted: Wed Apr 10, 2013 9:48 pm
by Roadie
What a great bike to have. Should be a good ride

Re: Started the KTM build

Posted: Thu Apr 11, 2013 8:05 pm
by Lots of steel bikes
Roadie wrote:What a great bike to have. Should be a good ride
The interesting part will be using friction shifters with a 10 speed cassette.

Re: Started the KTM build

Posted: Thu Apr 11, 2013 10:49 pm
by dv
The bike looks very nice, but I would question trying a 10 speed friction shift. (unless you are having a lend and I am slow....). For what it's worth I have an 8 and it's workable - just. It's pretty flat where I ride but I would hate to be doing quick changes in the hills. I think you stand a fair chance of damaging the cassette or chain. I have been told to try a 9 speed chain on my 8 speed set up to give me a little extra clearance. My favorite friction shifters are 5 and 6 speed, where I never have problems with gears jumping etc. anything more and indexed are (for me) definitely the go. I probably have not tried all combinations of chain cassette and derailleur....but I don't have my own bike shop either, so it still may be possible? Sometimes you just have to try stuff!
Good luck with it.
dv

Re: Started the KTM build

Posted: Fri Apr 12, 2013 4:32 pm
by morini
You need some retro friction Simplex shifters. They used to be the best in the business and still pull decent money second hand.

http://velobase.com/ViewComponent.aspx? ... 8000ac1ac6" onclick="window.open(this.href);return false;

Re: Started the KTM build

Posted: Fri Apr 12, 2013 7:17 pm
by Lots of steel bikes
dv wrote:The bike looks very nice, but I would question trying a 10 speed friction shift. (unless you are having a lend and I am slow....). For what it's worth I have an 8 and it's workable - just. It's pretty flat where I ride but I would hate to be doing quick changes in the hills. I think you stand a fair chance of damaging the cassette or chain. I have been told to try a 9 speed chain on my 8 speed set up to give me a little extra clearance. My favorite friction shifters are 5 and 6 speed, where I never have problems with gears jumping etc. anything more and indexed are (for me) definitely the go. I probably have not tried all combinations of chain cassette and derailleur....but I don't have my own bike shop either, so it still may be possible? Sometimes you just have to try stuff!
Good luck with it.
dv
Not having a lend. Won't be doing much hill climbing or racing therefore not worried about quick changes. Might take awhile for the added dexterity required to kick in. As an aside the Campy Triomphe shifters on my Daccordi shift beautifully.

Re: Started the KTM build

Posted: Fri Apr 12, 2013 7:20 pm
by Lots of steel bikes
morini wrote:You need some retro friction Simplex shifters. They used to be the best in the business and still pull decent money second hand.

http://velobase.com/ViewComponent.aspx? ... 8000ac1ac6" onclick="window.open(this.href);return false;
Good advice but hoping to stay with the Dura Ace theme.

Re: Started the KTM build

Posted: Sun Apr 21, 2013 12:33 pm
by Lots of steel bikes
I've got a feeling the forks I bought for the KTM are 27" not 700. The brake blocks at their furthest reach are right on the edge of the rim. Is there a difinitive way to measure the fork to know for sure? Thanks.

Re: Started the KTM build

Posted: Mon May 27, 2013 7:55 pm
by Lots of steel bikes
Discovered what should have been predictable problems with this build. The downtube shifters and 7400 rear derailleur works absolutely fine with the 10 speed cassette. But the 7400 front derailleur obviously has a wider cage than one designed for a 10 speed chain. When shifting up to the large chain ring the derailleur has to push the narrow chain a lot further to engage the teeth. So far in fact the outer plate contacts the crank arm. I'll try putting a bit of packing against the inner plate to narrow the gap and reduce the travel required to see if this fixes the problem. If that works I'll look for an elegant way to modify it permanently or look for a 10 speed derailleur.

The other problem is that the narrow chain can fall down between the chainrings when shifting between the rings when the chain is running to the middle sprockets. Doesn't do this on the workstand but did once on the test ride. Luckily going slow at the time so it didn't jam. Not such a problem. I rarely ever use the small chain ring. I'm a grinder. So I could (not while riding) engage the large ring then trim the deraileur back away from the crank arm.

Regarding the forks, I found that the wheel wasn't seated all the way into the dropouts. Once in properly the brake pads align perfectly on the rim.

Re: Started the KTM build

Posted: Mon May 27, 2013 11:04 pm
by jbchybridrider
Saro28 wrote:If it's not orange it's a lemon :lol: . I know the moto pedigree, any story to the cycling side of ktm? Yep, don't mind early DA.
Actually KTM motorcycles of this period were white with a blue seat and orange frame so it's perfect. Or are you meaning there motorcycles from this period were lemons as in unreliable. I had a few in the 80's and they were unreliable but still so nice to ride it seemed worth the extra maintenance at the time.
I have seen KTM bicycle frames for sale before and been tempted, I'm sure there easier to own and loving this one.

Re: Started the KTM build

Posted: Thu May 30, 2013 8:32 am
by QuangVuong
Lots of steel bikes wrote:Discovered what should have been predictable problems with this build. The downtube shifters and 7400 rear derailleur works absolutely fine with the 10 speed cassette. But the 7400 front derailleur obviously has a wider cage than one designed for a 10 speed chain. When shifting up to the large chain ring the derailleur has to push the narrow chain a lot further to engage the teeth. So far in fact the outer plate contacts the crank arm. I'll try putting a bit of packing against the inner plate to narrow the gap and reduce the travel required to see if this fixes the problem. If that works I'll look for an elegant way to modify it permanently or look for a 10 speed derailleur.

The other problem is that the narrow chain can fall down between the chainrings when shifting between the rings when the chain is running to the middle sprockets. Doesn't do this on the workstand but did once on the test ride. Luckily going slow at the time so it didn't jam. Not such a problem. I rarely ever use the small chain ring. I'm a grinder. So I could (not while riding) engage the large ring then trim the deraileur back away from the crank arm.

Regarding the forks, I found that the wheel wasn't seated all the way into the dropouts. Once in properly the brake pads align perfectly on the rim.
What shifters are you gonna use?

As with the old derailleur compatibility, I'm using the 90s 105 FD with 9 speed. I may upgrade to 10 speed, so how bad of a prob is it?

Re: Started the KTM build

Posted: Thu May 30, 2013 7:06 pm
by BRLVR.v2
Needs Brifters!

Cool frame though......

Re: Started the KTM build

Posted: Thu May 30, 2013 9:28 pm
by Lots of steel bikes
QuangVuong wrote:
Lots of steel bikes wrote:Discovered what should have been predictable problems with this build. The downtube shifters and 7400 rear derailleur works absolutely fine with the 10 speed cassette. But the 7400 front derailleur obviously has a wider cage than one designed for a 10 speed chain. When shifting up to the large chain ring the derailleur has to push the narrow chain a lot further to engage the teeth. So far in fact the outer plate contacts the crank arm. I'll try putting a bit of packing against the inner plate to narrow the gap and reduce the travel required to see if this fixes the problem. If that works I'll look for an elegant way to modify it permanently or look for a 10 speed derailleur.

The other problem is that the narrow chain can fall down between the chainrings when shifting between the rings when the chain is running to the middle sprockets. Doesn't do this on the workstand but did once on the test ride. Luckily going slow at the time so it didn't jam. Not such a problem. I rarely ever use the small chain ring. I'm a grinder. So I could (not while riding) engage the large ring then trim the deraileur back away from the crank arm.

Regarding the forks, I found that the wheel wasn't seated all the way into the dropouts. Once in properly the brake pads align perfectly on the rim.
What shifters are you gonna use?

As with the old derailleur compatibility, I'm using the 90s 105 FD with 9 speed. I may upgrade to 10 speed, so how bad of a prob is it?
Using Dura ace 7400 downtube shifters. Outer cage plate of FD touches the crank arm due to the wide cage width teamed with a narrow chain. So a reasonably bad problem without modifying the derailleur or trying a 10 speed FD.

Re: Started the KTM build

Posted: Fri May 31, 2013 5:19 am
by porkchops
I would think that it wouldn't matter what FD you're running, there should be sufficient clearances that the FD wouldn't touch the crank, are you running the correct width BB? Maybe you should consider going to the next width up, which would give you an extra .5mm clearance.

Re: Started the KTM build

Posted: Fri May 31, 2013 7:05 am
by munga
7sp chain width is 7.3mm
10s chain width is 6.2mm

1mm difference roughly. seems odd that it would rub your crank arm without shifting up.

Re: Started the KTM build

Posted: Fri May 31, 2013 7:05 am
by singlespeedscott
Lots of steel bikes wrote:
Roadie wrote:What a great bike to have. Should be a good ride
The interesting part will be using friction shifters with a 10 speed cassette.
I use friction downtube shifters with 10 speed Campagnolo with no issues. Down rube shifting usually requires some planning for shifts so it shouldn't be a problem. I think people have just got lazy and sloppy with how the shift and as such try to ride their downtube shifting bikes like they ride the modern bikes with ergo/sti levers. Besides you could just use these if you have any issues -
http://www.ribblecycles.co.uk/sp/road-t ... 0000000000" onclick="window.open(this.href);return false;

Re: Started the KTM build

Posted: Fri May 31, 2013 7:31 pm
by BRLVR.v2
singlespeedscott wrote: I use friction downtube shifters with 10 speed Campagnolo with no issues.
Then you need to change your username to 10speedScott to avoid false advertising. :wink:

Re: Started the KTM build

Posted: Fri May 31, 2013 7:41 pm
by singlespeedscott
Only on the hills or fast group rides do the gears come out :)

I like riding the ranges out the back of Brissie and some roads require some extra cogs and a freewheel.

Re: Started the KTM build

Posted: Fri May 31, 2013 7:43 pm
by Lots of steel bikes
porkchops wrote:I would think that it wouldn't matter what FD you're running, there should be sufficient clearances that the FD wouldn't touch the crank, are you running the correct width BB? Maybe you should consider going to the next width up, which would give you an extra .5mm clearance.
The BB width would make no difference. That doesn't change the ring to crank distance.

Re: Started the KTM build

Posted: Fri May 31, 2013 7:50 pm
by Lots of steel bikes
munga wrote:7sp chain width is 7.3mm
10s chain width is 6.2mm

1mm difference roughly. seems odd that it would rub your crank arm without shifting up.
It shifts up. The outer plate touches the crank once it's up. Absolutely fine if you stop pedalling and trim away from the crank. Thats why I think it is the extra travel required due to the narrow chain and wide cage. Will have a play on the weekend.

Re: Started the KTM build

Posted: Fri May 31, 2013 8:56 pm
by munga
get bendin'! or try and find a 10s clamp-on, or a kludgy clamp adaptor

Re: Started the KTM build

Posted: Sat Jun 01, 2013 12:05 pm
by gordy
Lots of steel bikes wrote:
Roadie wrote:What a great bike to have. Should be a good ride
The interesting part will be using friction shifters with a 10 speed cassette.
I am using current model DA 10 speed, down tube shifters on my Salsa.
Probably not what you were going for, but they work a treat.

Re: Started the KTM build

Posted: Sat Jun 01, 2013 5:56 pm
by Lots of steel bikes
So my experiment worked. Packing the inner plate a couple of mm fixed the problem. So will look for a modern Dura ace FD. Does anyone know the cage width difference between a FD for an 8 speed and a 10 speed. I hope it is a couple of mm.