[Ulairi]

I have bought a 2nd hand Haro 24 VGF for my son. Overall the components and design seem quite good - with one exception. It routes both derailleur shift cables via the front of the downtube behind the front wheel, then they pass around the lower edge of the BB via a plastic guide. The cables are bare all the way through this route.

I'm concerned that shifting will suffer because dirt from the front wheel will cause wear and increased friction where they plastic guide is.

Obviously a fully sealed cable system is one solution, but I don't want to spend $70 on something like a Gore Rideon kit (it would cost almost as much as the bike cost)!

I have used Jagwire Ripcord on my MTB and it has sheathing and nosed ferrules that seal the cable run. However, I can't seen how I could use this around the BB. The Ripcord housing would end up being the load bearing surface for the cable around the BB and I wonder whether the cable may start to cut into the housing before too long.

Is there a replacement plastic guide that is sealed that the Jagwire could mate with?

What other cheap options exist to 'dirt proof' this type of cable routing? Or do we just have to be careful with cleaning after each ride?

Thanks

 

[frdfandc]

Usually you are limited to the routing of the cables that the manufacturer has designed.

Unless your handy with welding aluminum, there really isn't any options.

Best option is to just keep it clean. There is very little drag in the BB area on a bare cable. Most drag comes when dirt is inside the cables.

 

[mtnbiker72]

Full housing to the derailleur...use zip ties

 

[Squash]

I've never found it to be that big of an issue. Specialized used to use down tube cable routing on just about all their bikes including their FS designs. Since they've started using a lot of swoopy hydro formed tubes they've gone to routing under the top tube. And a few other manufacturers still down tube routing as well. I've ridden/owned quite a few MTBs with down tube routed shift cables and never had any problems with it. I've ridden them in everything from mud to desert dusty sand to beach sand with 0 issues. The key is just keeping it clean. After a muddy or very dusty ride simply release the tension on both derailleurs and clean the bike as you normally would. And occasionally, maybe once a month if you ride daily, a SINGLE drop of Triflow or similar lube on the cable where it sits in the center of the cable guide is all that is necessary to keep things running smoothly. The only problem I've ever had with the down tube routing is in sloppy winter conditions. I've had enough slush or wet snow build up to freeze the cables solid in the guide. Otherwise no problems.

If you do have issues or it does concern you that much, as mtbiker72 noted, you can run full length housing using zip ties or stick on cable guides. But unless the bike is going to be ridden in some very extreme conditions, or maintenance will be lacking, I don't think you'll have problems.

Good Dirt

 

[Ulairi]

I've never found it to be that big of an issue. ....After a muddy or very dusty ride simply release the tension on both derailleurs and clean the bike as you normally would. And occasionally, maybe once a month if you ride daily, a SINGLE drop of Triflow or similar lube on the cable where it sits in the center of the cable guide is all that is necessary to keep things running smoothly.

Thanks Squash - that is very helpful.

Looking for options on the net since making the OP reveals that these type of guides are a lot more common than I thought. It seems to be a design carry-over from road bikes. I had started to reach the same conclusion that the best option may be to simply replace the guide (they are cheap) and keep it clean.

It just seems like a silly place to run the cables! Muck from the front wheel will build up there very quickly. Even on a road bike ...

Thanks, also, to mtnbiker72 and frdfandc.

 

[gmcttr]

Your son will out grow the bike before the cable guide needs to be replaced. Forget about it and go ride.

 

[Klein_man]

My 07 hifi has them under the BB. I raced several times in muddy conditions and the shifting issues came from the cassette being caked in mud, not the the cables under the BB.

 

[shiggy]

Thanks Squash - that is very helpful.

Looking for options on the net since making the OP reveals that these type of guides are a lot more common than I thought. It seems to be a design carry-over from road bikes. I had started to reach the same conclusion that the best option may be to simply replace the guide (they are cheap) and keep it clean.

It just seems like a silly place to run the cables! Muck from the front wheel will build up there very quickly. Even on a road bike ...

Thanks, also, to mtnbiker72 and frdfandc.

The under BB routing actually works very well and is not very affected by dirt, water or muck. Requires fewer braze ons or clamps. Uses little housing so it is more compression resistant and lighter.

Main issue is the RD cable can interfere with the rear tire.

 

[Squash]

Thanks Squash - that is very helpful.

Looking for options on the net since making the OP reveals that these type of guides are a lot more common than I thought. It seems to be a design carry-over from road bikes. I had started to reach the same conclusion that the best option may be to simply replace the guide (they are cheap) and keep it clean.

It just seems like a silly place to run the cables! Muck from the front wheel will build up there very quickly. Even on a road bike ...

Thanks, also, to mtnbiker72 and frdfandc.

Your welcome.

The under bb routing is a hold over from the early days of MTB production when MTB frames were pretty much road bike frames with flat bars, fat tires, and heavier duty tubing. But as the others have posted, it works just fine. :thumbsup:

Good Dirt