700c rear wheel, pro's & con's

[spennie]

I'm thinking of putting a 700c rear wheel on my ice sprint, at the moment I ride on a 26". I,ve noticed a lot of faster trikes have 700c rear, l was just wondering what the pro's & con's would be putting one on my trike.

 

[Smokin Joe]

My Performer came with a 700c as standard. As I've never ridden with any other size I can't tell you whether it is better or not, but the choice and availability of tyres and tubes is one major advantage.

 

[PaulM]

The Sprint is quite a firm ride. I'd keep the cushier tyre.

 

[Mr Magoo]

I'm thinking of putting a 700c rear wheel on my ice sprint, at the moment I ride on a 26". I,ve noticed a lot of faster trikes have 700c rear, l was just wondering what the pro's & con's would be putting one on my trike.

Key question .......do you wish to carry luggage via a rack and panniers and how much do you weigh
If you change the rear ......which looks like a simple tempting mod
....you will need to consider changing the front wheels or the handling will be all over the place @!#$%
For example the ICE VTX 700 rear 28x622fronts are 18x406
VTX PLUS has 700 rear 23x622 fronts are 23x406
Look close at the VTX and you will find the front seat mount is lower than the Sprint series
Whilst your at it .......the higher cornering G loads .......that you will soon discover !
Will result in serious thoughts about a bucket sea shell as offered by ICE and of course used by Windcheetahs
If you wish to improve the Sprint .........a quick diet will help ........don't overlook the chain weight (probably the simplest mod but often overlooked )
These so called quick machines do not fold ......hence a further weight saving
I have two examples of " lean and mean trikes " to show it can be done and has been done years ago .
One is a Custom built ICE Trike built in 2003 (the bar end shifters have been machined down and all the fixings are Ti or Ali ) and weighs less than a VTX !
Two is a 1992 Windcheetah carbon free and yet lighter than the 2016 Spezi show model
one clue how it achieves this
........ the casting are machined on the outside rather than rough sand cast finish ....to save weight !
Pop a picture up of your current setup and confirm the mechanical spec and I might be able to suggest suitable mods .
Food for thought ?

 

[PaulM]

I was thinking there would not be much difference in diameter between a 559 wheel with a 40 mm tyre and a 700 wheel with a 25 mm tyre. But it might be enough to make the trike oversteer with the reduced trail. You can get Conti GP tyres in both 559 and 406 with 28mm width I think, which would lighten and speed things up a bit.

 

[spennie]

Key question .......do you wish to carry luggage via a rack and panniers and how much do you weigh
If you change the rear ......which looks like a simple tempting mod
....you will need to consider changing the front wheels or the handling will be all over the place @!#$%
For example the ICE VTX 700 rear 28x622fronts are 18x406
VTX PLUS has 700 rear 23x622 fronts are 23x406
Look close at the VTX and you will find the front seat mount is lower than the Sprint series
Whilst your at it .......the higher cornering G loads .......that you will soon discover !
Will result in serious thoughts about a bucket sea shell as offered by ICE and of course used by Windcheetahs
If you wish to improve the Sprint .........a quick diet will help ........don't overlook the chain weight (probably the simplest mod but often overlooked )
These so called quick machines do not fold ......hence a further weight saving
I have two examples of " lean and mean trikes " to show it can be done and has been done years ago .
One is a Custom built ICE Trike built in 2003 (the bar end shifters have been machined down and all the fixings are Ti or Ali ) and weighs less than a VTX !
Two is a 1992 Windcheetah carbon free and yet lighter than the 2016 Spezi show model
one clue how it achieves this
........ the casting are machined on the outside rather than rough sand cast finish ....to save weight !
Pop a picture up of your current setup and confirm the mechanical spec and I might be able to suggest suitable mods .
Food for thought ?

I've just finished upgrading my 2010 trike this summer.what i've done is changed the wheelset to the DA16s on duranno tyres(90psi front, 100 rear)S/A hub brakes to bb7 disc brakes,Swapped the old hardshell seat to the new lighter shell, 105 triple chainset which i might change to a double next year( as i live in north norfolk), sram x9 carbon rear mech and sram 900 gear levers.I only carry tools & Spare inner tubes and only do 20- 40 mile rides,so i don't really need much else.

 

[PaulM]

DA16s are heavier than X101s, discs are less aerodynamic than drums. Looks like you've removed the rear brake already. You could get a lighter rear hub and rim, TRP Spyres (Spykes for MTB levers I think) are lighter than BB7s. Consider an 11-speed set up with an 11-42T cassette and compact double with a manual change? Otherwise titanium fasteners?

 

[Mr Magoo]

View attachment 147336
I've just finished upgrading my 2010 trike this summer.what i've done is changed the wheelset to the DA16s on duranno tyres(90psi front, 100 rear)S/A hub brakes to bb7 disc brakes,Swapped the old hardshell seat to the new lighter shell, 105 triple chainset which i might change to a double next year( as i live in north norfolk), sram x9 carbon rear mech and sram 900 gear levers.I only carry tools & Spare inner tubes and only do 20- 40 mile rides,so i don't really need much else.

First thing to say its a very nice trike
Its "Bootifull" and ideal for them there "Roman Roods" and pot holes to be found in Norfolk
Have you weighed the revised sprint in the picture ....my estimate is 39lbs ???
The VTX with similar extras fitted ........my estimate 35 lbs
How to claw back the 4lbs ................go the aero route ....see below
What is the brand and type of chain fitted .....so you could compare gram weight savings with higher quality chains ....you may be surprised
Consider moving from 9 to 10 speed via double ring front and 10 cogs
Change the mirrors to the smaller VTX oblong pattern to reduce drag !
Change the fixing bolts to Ti + Alu (speak to ICE first about loadings ) and replace the front axles with ICE Ti replacements
Suggest stick a small front fairing on yours and achieve a possible 5% aero gain and warmer feet by a few degrees
Perhaps a tailsock fairing to tidy up the rear aerodynamics ? %
Paul M ................tried big front wheels on his ICE Sprint and achieved ??????...........I'll let PM reveal his findings

 

[PaulM]

I put 26" Mavic disc rims on the front with double butted spokes (and rear disc rim even though no rear brake - lighter rims you see), and fitted folding tyres all round (Kojaks from memory). This made the seat more reclined - downhill speeds increased. Comfort improved and the higher seat made it easier to mount/dismount. The steering became heavier but not a problem. I managed to get it on 2 wheels once while some cornering at speed - no real drama. I think the tracking was more critical with the large front wheels and altered geometry. I tried for zero toe in. It was fine but if I took both hands off the bars and the trike hit a bump it could go into a mild shimmy - maybe a small toe-in would have helped. In theory the larger front wheels should have reduced rolling resistance. With hindsight I'm a bit more sceptical of the benefits but others swear by it. I sold the trike because I became weary of the weight (around 39lbs with rack and mesh seat - plus 3lb D-lock plus tools etc) on my commute which has a long hill. Have a Catrike 700 now (new model with 406 rims on the front) which is lighter and faster for me.

 

[PaulM]

TBH, I considered hollow-pin chains and Ti axles and decided the weight saving wasn't worth it - maybe 100g total for the former and 80 g per axle for the latter (perhaps less .... getting old, memory going). But 10/11 speed chains will be lighter than 9 speed, so moving to an 11 speed single chainring set up would be one way to go (or make it a double with a Fred Flintstone finger shift).

 

[spennie]

Cheers guys, you've given me some good ideas to try out next spring. All i've got to do now is get the miles in and keep away from the christmas chocolates.